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    338 Products

    Cap Nuts

    Conceal and protect protruding screw threads while fastening parts together. These nuts help prevent damage to surrounding materials and reduce injuries. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating. They resist rust in wet and outdoor environments but won't hold up to the harsh chemicals that 316 stainless steel can.
    Super-Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant cap nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Pkg.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    0-80
    1/16"3/16"3/16"191855A101000000000000000
    1-72
    1/16"3/16"3/16"191855A102000000000000
    2-56
    5/64"3/16"3/16"191855A103000000000000
    3-48
    5/64"1/4"1/4"191855A104000000000000
    4-40
    5/32"1/4"1/4"1099022A101000000000000
    4-48
    5/32"1/4"1/4"1091855A67000000000000000
    5-40
    1/8"5/16"11/32"191855A105000000000000
    6-32
    5/32"5/16"11/32"1091855A430000000000000
    6-32
    3/16"5/16"9/32"1099022A102000000000000
    6-40
    5/32"5/16"11/32"1091855A680000000000000000
    8-32
    5/32"5/16"11/32"1091855A440000000000000
    8-32
    3/16"5/16"9/32"1099022A103000000000000
    8-36
    5/32"5/16"11/32"1091855A690000000000000000
    10-24
    3/16"3/8"13/32"1091855A450000000000000
    10-24
    7/32"3/8"11/32"1099022A1040000000000000
    10-32
    3/16"3/8"13/32"1091855A460000000000000
    10-32
    7/32"3/8"11/32"1099022A1050000000000000
    12-24
    7/32"3/8"13/32"1091855A410000000000000
    12-28
    7/32"3/8"13/32"191855A640000000000000
    1/4"-20
    7/32"7/16"3/8"1099022A106000000000000000
    1/4"-20
    1/4"7/16"15/32"1091855A5200000000000000
    1/4"-20
    5/16"7/16"19/32"1091855A3600000000000000
    1/4"-28
    7/32"7/16"3/8"1099022A107000000000000000
    1/4"-28
    1/4"7/16"15/32"1091855A4700000000000000
    5/16"-18
    9/32"9/16"7/16"599022A1080000000000000
    5/16"-18
    5/16"1/2"17/32"1091855A54000000000000000
    5/16"-24
    9/32"9/16"7/16"599022A1090000000000000
    5/16"-24
    5/16"1/2"17/32"1091855A032000000000000000
    3/8"-16
    5/16"5/8"1/2"599022A112000000000000000
    3/8"-16
    3/8"9/16"5/8"591855A5500000000000000
    3/8"-24
    5/16"5/8"1/2"599022A113000000000000000
    3/8"-24
    3/8"9/16"5/8"591855A3310000000000000
    7/16"-14
    3/8"3/4"9/16"199022A114000000000000
    7/16"-14
    7/16"5/8"11/16"191855A560000000000000
    7/16"-20
    3/8"3/4"9/16"199022A115000000000000
    7/16"-20
    7/16"5/8"11/16"191855A490000000000000
    1/2"-13
    3/8"3/4"9/16"199022A116000000000000
    1/2"-13
    1/2"3/4"13/16"191855A480000000000000
    1/2"-20
    3/8"3/4"9/16"199022A126000000000000
    1/2"-20
    1/2"3/4"13/16"191855A333000000000000
    9/16"-12
    9/16"7/8"15/16"191855A11200000000000000
    9/16"-18
    9/16"7/8"15/16"191855A11300000000000000
    5/8"-11
    7/16"15/16"3/4"199022A117000000000000000
    5/8"-11
    5/8"15/16"1"191855A4200000000000000
    5/8"-18
    5/8"15/16"1"191855A5100000000000000
    3/4"-10
    1/2"1 1/16"7/8"199022A118000000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"191855A530000000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"191855A114000000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"191855A115000000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"191855A116000000000000000
    1"-8
    1"1 7/16"1 35/64"191855A117000000000000000
    1"-14
    1"1 7/16"1 33/64"191855A700000000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"191855A650000000000000000
    M3 × 0.5 mm3.8 mm5.5 mm6 mmDIN 15871094000A330000000000000
    M4 × 0.7 mm5.7 mm7 mm8 mmDIN 15872594000A035000000000000
    M5 × 0.8 mm4.5 mm8 mm10 mmDIN 15872594000A037000000000000
    M6 × 1 mm7.7 mm10 mm12 mmDIN 15872094000A038000000000000
    M8 × 1.25 mm10.7 mm13 mm15 mmDIN 15871094000A039000000000000
    M10 × 1.5 mm12.7 mm17 mm18 mmDIN 1587594000A040000000000000
    M12 × 1.75 mm15.7 mm19 mm22 mmDIN 1587594000A041000000000000
    M14 × 2 mm17.7 mm22 mm25 mmDIN 1587194000A431000000000000
    M16 × 2 mm20.6 mm24 mm28 mmDIN 1587194000A461000000000000
    M18 × 2.5 mm24.6 mm27 mm32 mmDIN 1587194000A490000000000000
    M20 × 2.5 mm25.6 mm30 mm34 mmDIN 1587194000A510000000000000
    M22 × 2.5 mm28.6 mm34 mm39 mmDIN 1587194000A101000000000000
    M24 × 3 mm30.5 mm36 mm42 mmDIN 1587194000A102000000000000
     
    Black-Oxide 18-8 Stainless Steel
    6-32
    5/32"5/16"11/32"1091855A1210000000000000
    8-32
    5/32"5/16"11/32"1091855A1220000000000000
    10-24
    3/16"3/8"13/32"1091855A12300000000000000
    10-32
    3/16"3/8"13/32"1091855A12400000000000000
    1/4"-20
    1/4"7/16"15/32"1091855A125000000000000000
    5/16"-18
    5/16"1/2"17/32"591855A1260000000000000
    3/8"-16
    3/8"9/16"5/8"191855A127000000000000
    1/2"-13
    1/2"3/4"13/16"191855A128000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    2-56
    5/64"3/16"3/16"192994A1010000000000000
    4-40
    5/32"1/4"1/4"592994A0050000000000000
    5-40
    1/8"5/16"11/32"192994A128000000000000
    6-32
    5/32"5/16"11/32"592994A0070000000000000
    8-32
    5/32"5/16"11/32"592994A0090000000000000
    10-24
    3/16"3/8"13/32"592994A40100000000000000
    10-32
    3/16"3/8"13/32"592994A40200000000000000
    12-24
    7/32"3/8"13/32"192994A133000000000000
    1/4"-20
    1/4"7/16"15/32"192994A029000000000000
    1/4"-28
    1/4"7/16"15/32"192994A329000000000000
    5/16"-18
    5/16"1/2"17/32"192994A030000000000000
    5/16"-24
    5/16"1/2"17/32"192994A330000000000000
    3/8"-16
    3/8"9/16"5/8"192994A031000000000000
    3/8"-24
    3/8"9/16"5/8"192994A331000000000000
    7/16"-14
    7/16"5/8"11/16"192994A111000000000000
    7/16"-20
    7/16"5/8"11/16"192994A112000000000000
    1/2"-13
    1/2"3/4"13/16"192994A033000000000000
    1/2"-20
    1/2"3/4"13/16"192994A034000000000000
    9/16"-12
    9/16"7/8"15/16"192994A135000000000000000
    9/16"-18
    9/16"7/8"15/16"192994A136000000000000000
    5/8"-11
    5/8"15/16"1"192994A035000000000000000
    5/8"-18
    5/8"15/16"1"192994A113000000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"192994A038000000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"192994A114000000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"192994A137000000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"192994A138000000000000000
    1"-8
    1"1 7/16"1 35/64"192994A139000000000000000
    1"-12
    1"1 7/16"1 35/64"192994A141000000000000000
    1"-14
    1"1 7/16"1 35/64"192994A142000000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"192994A143000000000000000
    1 1/4"-12
    1 1/4"1 13/16"1 61/64"192994A144000000000000000
    M3 × 0.5 mm3.8 mm5.5 mm6 mmDIN 15872595514A101000000000000
    M4 × 0.7 mm5.5 mm7 mm8 mmDIN 15872595514A102000000000000
    M5 × 0.8 mm4.5 mm8 mm10 mmDIN 15872595514A103000000000000
    M6 × 1 mm8 mm10 mm12 mmDIN 15872595514A1040000000000000
    M8 × 1.25 mm11 mm13 mm15 mmDIN 15871095514A105000000000000
    M10 × 1.5 mm13 mm17 mm18 mmDIN 15871095514A106000000000000000
    M12 × 1.75 mm16 mm19 mm22 mmDIN 1587595514A107000000000000000
    M14 × 2 mm18 mm22 mm25 mmDIN 1587195514A108000000000000
    M16 × 2 mm21 mm24 mm28 mmDIN 1587195514A109000000000000
    M20 × 2.5 mm26 mm30 mm34 mmDIN 1587195514A11100000000000000
    M22 × 2.5 mm29 mm34 mm39 mmDIN 1587195514A112000000000000000
    M24 × 3 mm31 mm36 mm42 mmDIN 1587195514A113000000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black Corrosion-Resistant-Coated Steel—Combines a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Nickel-Plated Steel—This plating resists salt water and chemicals better than zinc plating and is less likely to wear off. It also has a bright, polished appearance.
    Chrome-Plated Steel—The brightest, shiniest finish we offer, this plating has a mirror-like appearance that is often used in decorative applications. It resists salt water and chemicals better than zinc plating and is less likely to wear off.
    Pkg.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    2-56
    5/32"1/4"1/4"2591875A101000000000000000
    3-48
    5/32"1/4"1/4"1091875A281000000000000
    4-40
    5/32"1/4"1/4"5091875A105000000000000000
    4-48
    5/32"1/4"1/4"1091875A284000000000000
    5-40
    5/32"5/16"11/32"1091875A321000000000000
    6-32
    5/32"5/16"11/32"5091875A11000000000000000
    6-40
    5/32"5/16"11/32"1091875A469000000000000
    8-32
    5/32"5/16"11/32"5091875A11500000000000000
    8-36
    5/32"5/16"11/32"1091875A710000000000000
    10-24
    3/16"3/8"13/32"5091875A120000000000000000
    10-32
    3/16"3/8"13/32"5091875A125000000000000000
    1/4"-20
    1/4"7/16"15/32"2591875A1300000000000000
    1/4"-28
    1/4"7/16"15/32"2591875A1350000000000000
    5/16"-18
    5/16"1/2"17/32"2591875A14000000000000000
    5/16"-24
    5/16"1/2"17/32"2591875A14500000000000000
    3/8"-16
    3/8"9/16"5/8"2591875A150000000000000000
    3/8"-24
    3/8"9/16"5/8"2591875A155000000000000000
    7/16"-14
    7/16"5/8"11/16"2091875A160000000000000000
    7/16"-20
    7/16"5/8"11/16"2091875A165000000000000000
    1/2"-13
    1/2"3/4"13/16"1091875A1700000000000000
    1/2"-20
    1/2"3/4"13/16"1091875A1750000000000000
    5/8"-11
    5/8"15/16"1"591875A1800000000000000
    5/8"-18
    5/8"15/16"1"591875A1850000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"191875A190000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"191875A195000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"191875A102000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"191875A103000000000000
    1"-8
    1"1 7/16"1 35/64"191875A038000000000000
    1"-14
    1"1 7/16"1 35/64"191875A104000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"191875A106000000000000000
    1 1/4"-12
    1 1/4"1 13/16"1 61/64"191875A107000000000000000
    M4 × 0.7 mm5.3 mm7 mm8 mmDIN 15875091880A03500000000000000
    M5 × 0.8 mm3.7 mm8 mm10 mmDIN 15875091880A03700000000000000
    M6 × 1 mm7.7 mm10 mm12 mmDIN 15875091880A045000000000000000
    M8 × 1.25 mm10.7 mm13 mm15 mmDIN 15872591880A0500000000000000
    M10 × 1.5 mm12.7 mm17 mm18 mmDIN 15871091880A056000000000000
    M12 × 1.75 mm15.7 mm19 mm22 mmDIN 15871091880A06000000000000000
     
    Black Corrosion-Resistant-Coated Steel
    4-40
    5/32"1/4"1/4"1098667A10100000000000000
    6-32
    5/32"5/16"11/32"1098667A11000000000000000
    8-32
    5/32"5/16"11/32"1098667A130000000000000000
    10-24
    3/16"3/8"13/32"598667A150000000000000
    10-32
    3/16"3/8"13/32"598667A190000000000000
    1/4"-20
    1/4"7/16"15/32"598667A210000000000000
    5/16"-18
    5/16"1/2"17/32"598667A2300000000000000
    3/8"-16
    3/8"9/16"5/8"198667A250000000000000
    7/16"-14
    7/16"5/8"11/16"198667A601000000000000
    1/2"-13
    1/2"3/4"13/16"198667A102000000000000
    9/16"-12
    9/16"7/8"15/16"198667A695000000000000
    5/8"-11
    5/8"15/16"1"198667A706000000000000
     
    Nickel-Plated Steel
    6-32
    5/32"5/16"1/4"10090532A1000000000000000
    8-32
    5/32"5/16"1/4"10090532A1250000000000000
    10-24
    3/16"3/8"5/16"10090532A150000000000000
    10-32
    3/16"3/8"5/16"10090532A17500000000000000
    1/4"-20
    1/4"7/16"3/8"10090532A200000000000000000
    5/16"-18
    5/16"9/16"15/32"5090532A22500000000000000
    3/8"-16
    3/8"5/8"1/2"2590532A250000000000000
    1/2"-13
    1/2"3/4"9/16"2590532A275000000000000000
    5/8"-11
    5/8"15/16"13/16"1090532A300000000000000000
    3/4"-10
    3/4"1 1/8"1 1/8"190532A325000000000000
     
    Chrome-Plated Steel
    M4 × 0.7 mm3.9 mm7 mm8 mmDIN 1587591982A2000000000000000
    M5 × 0.8 mm5.6 mm8 mm10 mmDIN 1587591982A2250000000000000
    M6 × 1 mm5.7 mm10 mm12 mmDIN 1587591982A25000000000000000
    M8 × 1.25 mm8.2 mm13 mm15 mmDIN 1587191982A275000000000000
    M10 × 1.5 mm9.7 mm17 mm18 mmDIN 1587191982A300000000000000
    M12 × 1.75 mm12.2 mm19 mm22 mmDIN 1587191982A325000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    About twice as strong as low-strength steel, these Grade 5 nuts fasten most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black Corrosion-Resistant-Coated Steel—Combines a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Pkg.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 5
    1098858A101000000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 5
    1098858A1020000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 5
    1098858A103000000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 5
    598858A104000000000000000
    5/8"-11
    5/8"15/16"1"SAE Grade 5
    198858A105000000000000
    3/4"-10
    3/4"1 1/8"1 5/32"SAE Grade 5
    198858A106000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"SAE Grade 5
    198858A291000000000000000
    1"-8
    1"1 1/2"1 35/64"SAE Grade 5
    198858A107000000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 5
    198858A558000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 5
    198858A570000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 5
    198858A640000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 5
    198858A84900000000000000
     
    High-Strength Steel
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Rated Grade 8 or Class 10, these nuts are about 25% stronger than medium-strength steel nuts. They are commonly used to fasten components in valves, pumps, motors, and other high-stress applications. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black Corrosion-Resistant-Coated Steel—Combines a finished appearance with the rust resistance of stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    Pkg.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 8
    1090100A1010000000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 8
    1090100A10200000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 8
    1090100A103000000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 8
    190100A104000000000000
    5/8"-11
    5/8"15/16"1"SAE Grade 8
    190100A105000000000000
    3/4"-10
    3/4"1 1/8"1 5/32"SAE Grade 8
    190100A106000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"SAE Grade 8
    190100A108000000000000000
    1"-8
    1"1 1/2"1 35/64"SAE Grade 8
    190100A107000000000000000
    M6 × 1 mm5.7 mm10 mm12 mmISO Class 10
    DIN 1587599164A10100000000000000
    M8 × 1.25 mm8.2 mm13 mm15 mmISO Class 10
    DIN 1587599164A102000000000000000
    M10 × 1.5 mm9.7 mm17 mm18 mmISO Class 10
    DIN 1587199164A103000000000000
    M12 × 1.75 mm12.2 mm19 mm22 mmISO Class 10
    DIN 1587199164A1040000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 8
    190767A111000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 8
    190767A112000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 8
    190767A113000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 8
    190767A11400000000000000
     

    Cap Nut Assortments

    Image of Product. Front orientation. Cap Nuts. Cap Nut Assortments.
    Image of Product. Front orientation. ZoomedIn view. Cap Nuts. Cap Nut Assortments.
    With a range of sizes on hand, you can use these assortments to conceal and protect protruding screw threads while fastening a variety of parts. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Nickel-Plated Steel—This plating resists salt water and chemicals better than zinc plating and is less likely to wear off. It also has a bright, polished appearance.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread Size
    No. of
    Pieces
    Container
    Type
    Each
    Nickel-Plated Steel
    6-32, 8-32, 10-32, 1/4"-20, 5/16"-18, 3/8"-16
    200Plastic Box91987A300000000
     
    18-8 Stainless Steel
    6-32, 8-32, 10-32, 1/4"-20, 5/16"-18, 3/8"-16
    200Plastic Box91987A800000000
     

    Nylon-Insert Cap Nuts

    Get the protection of a cap nut with the vibration resistance of a locknut. These nuts not only conceal protruding screw threads, they also have a nylon insert that grips the screw to prevent loosening from moderate vibration. However, the insert may become brittle if exposed to high temperatures. Nuts are reusable a handful of times, but their holding power decreases with each use.
    Low-Strength Steel
    Image of Product. Bottom orientation. Cap Nuts. Nylon-Insert Cap Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Nylon 6/6 Cap—The nylon cap on these nuts is softer than metal, so it's less likely to scratch surrounding surfaces or parts.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm2.3 mm7 mm9.6 mmISO Class 6
    DIN 9862455090582A111000000
    M5 × 0.8 mm3.5 mm8 mm10.5 mmISO Class 6
    DIN 9862452590582A1120000
    M6 × 1 mm3.9 mm10 mm12 mmISO Class 6
    DIN 9862452590582A1130000
    M8 × 1.25 mm5.2 mm13 mm14 mmISO Class 6
    DIN 9862452590582A11400000
    M10 × 1.5 mm6.4 mm16 mm18 mmISO Class 6
    DIN 9862451090582A11500000
    M12 × 1.75 mm8.3 mm18 mm23 mmISO Class 6
    DIN 986245590582A1160000
    M16 × 2 mm11.3 mm24 mm28 mmISO Class 6
    DIN 986245190582A1170000
    M20 × 2.5 mm13.5 mm30 mm35 mmISO Class 6
    DIN 986245190582A1180000
     
    Zinc-Plated Steel with Nylon 6/6 Cap
    8-32
    9/64"11/32"23/64"SAE Grade 2
    2502598190A1300000
    10-24
    9/64"3/8"23/64"SAE Grade 2
    2502598190A1500000
    10-32
    9/64"3/8"23/64"SAE Grade 2
    2502598190A1700000
    1/4"-20
    7/32"7/16"31/64"SAE Grade 2
    2502598190A1900000
    5/16"-18
    1/4"1/2"1/2"SAE Grade 2
    2501098190A2100000
    3/8"-16
    21/64"9/16"5/8"SAE Grade 2
    2502598190A11100000
     
    Steel with Nylon 6/6 Cap
    8-32
    9/64"11/32"23/64"SAE Grade 2
    2502598190A1120000
    10-32
    9/64"3/8"23/64"SAE Grade 2
    2502598190A1130000
    1/4"-20
    7/32"7/16"31/64"SAE Grade 2
    2502598190A1140000
    1/4"-28
    7/32"7/16"31/64"SAE Grade 2
    2502598190A1150000
    5/16"-24
    1/4"1/2"1/2"SAE Grade 2
    2502598190A1160000
    3/8"-24
    21/64"9/16"5/8"SAE Grade 2
    2502598190A11700000
     
    Medium-Strength Steel
    Image of Product. Bottom orientation. Cap Nuts. Nylon-Insert Cap Nuts.
    About twice as strong as low-strength steel, these Grade 5 nuts fasten most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Nylon 6/6 Cap—The nylon cap on these nuts is softer than metal, so it's less likely to scratch surrounding surfaces or parts.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel with Nylon 6/6 Cap
    3/8"-24
    21/64"9/16"5/8"SAE Grade 5
    2501098190A270000000
     

    Cap Nuts with Threadlocker

    These nuts not only conceal and protect protruding screw threads, they also resist loosening from mild vibration. They have a nylon patch bonded to their threads that grips screws for a tighter hold than standard cap nuts. They’re reusable a handful of times, but the patch’s holding power decreases with each use. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    Image of Product. Front orientation. Contains Annotated, Border. Cap Nuts. Cap Nuts with Threadlocker.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating. They resist rust in wet and outdoor environments but won't hold up to the harsh chemicals that 316 stainless steel can.
    Super-Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant cap nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-24
    3/16"3/8"13/32"590421A110000000
    10-32
    3/16"3/8"13/32"590421A12000000
    12-24
    7/32"3/8"13/32"590421A13000000
    1/4"-20
    1/4"7/16"15/32"590421A14000000
    1/4"-28
    1/4"7/16"15/32"590421A15000000
    5/16"-18
    19/64"1/2"17/32"590421A16000000
    3/8"-16
    3/8"9/16"5/8"590421A17000000
    3/8"-24
    3/8"9/16"5/8"590421A18000000
    7/16"-14
    7/16"5/8"45/64"190421A1900000
    1/2"-13
    1/2"3/4"13/16"190421A2100000
    5/8"-11
    5/8"15/16"1"190421A22000000
    3/4"-10
    3/4"1 1/16"1 5/32"190421A23000000
    M5 × 0.8 mm5.6 mm8 mm10 mmDIN 1587590428A11000000
    M6 × 1 mm5.7 mm10 mm12 mmDIN 1587590428A12000000
    M8 × 1.25 mm8.2 mm13 mm15 mmDIN 1587590428A13000000
    M10 × 1.5 mm9.7 mm17 mm18 mmDIN 1587190428A14000000
    M12 × 1.75 mm12.2 mm19 mm22 mmDIN 1587190428A15000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    3/16"3/8"13/32"590421A32000000
    1/4"-20
    1/4"7/16"15/32"590421A34000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    10-24
    3/16"3/8"13/32"593052A11000000
    10-32
    3/16"3/8"13/32"593052A12000000
    1/4"-20
    1/4"7/16"15/32"593052A13000000
    5/16"-18
    5/16"1/2"17/32"193052A1400000
    3/8"-16
    3/8"9/16"5/8"193052A1500000
    1/2"-13
    1/2"3/4"13/16"193052A16000000
    5/8"-11
    5/8"15/16"1"193052A17000000
     

    Distorted-Thread Cap Nuts

    For a stronger hold than nylon-insert cap nuts, these have irregularly shaped threads that grip the screw to resist loosening. The threads prevent the nut from backing out in high-vibration applications, but they also increase the effort to install and remove. To get these nuts off, you may need special tools, such as an impact wrench or propane torch. They have a smooth, rounded head that conceals and protects protruding screw threads while creating a finished look. Nuts are not reusable.
    Stainless Steel
    Image of Product. Bottom orientation. Cap Nuts. Distorted-Thread Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Super-Corrosion-Resistant 316 Stainless Steel—Our most corrosion-resistant cap nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    4-40
    5/32"1/4"1/4"1090507A209000000
    6-32
    5/32"5/16"11/32"1090507A21000000
    8-32
    5/32"5/16"11/32"1090507A21500000
    10-24
    3/16"3/8"13/32"1090507A22000000
    10-32
    3/16"3/8"13/32"1090507A22500000
    1/4"-20
    1/4"7/16"15/32"1090507A23000000
    1/4"-28
    1/4"7/16"15/32"1090507A23500000
    5/16"-18
    5/16"1/2"17/32"590507A24000000
    5/16"-24
    5/16"1/2"17/32"590507A24500000
    3/8"-16
    3/8"9/16"5/8"590507A25000000
    3/8"-24
    3/8"9/16"5/8"590507A25500000
    7/16"-14
    7/16"5/8"11/16"190507A2750000
    7/16"-20
    7/16"5/8"11/16"190507A2760000
    1/2"-13
    1/2"3/4"13/16"190507A03300000
    1/2"-20
    1/2"3/4"13/16"190507A04400000
    5/8"-11
    19/32"1"63/64"190507A2600000
    3/4"-10
    11/16"1 1/16"1 3/16"190507A2700000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    8-32
    5/32"5/16"11/32"190431A1100000
    10-24
    3/16"3/8"13/32"190431A1200000
    10-32
    3/16"3/8"13/32"190431A1300000
    1/4"-20
    1/4"7/16"15/32"190431A1400000
    5/16"-18
    5/16"1/2"17/32"190431A1500000
    3/8"-16
    3/8"9/16"5/8"190431A1600000
    1/2"-13
    1/2"3/4"13/16"190431A17000000
     
    Low-Strength Steel
    Image of Product. Bottom orientation. Cap Nuts. Distorted-Thread Cap Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    6-32
    5/32"5/16"11/32"SAE Grade 2
    5090455A110000000
    8-32
    5/32"5/16"11/32"SAE Grade 2
    5090455A12000000
    10-24
    3/16"3/8"13/32"SAE Grade 2
    2590455A13000000
    10-32
    3/16"3/8"13/32"SAE Grade 2
    2590455A14000000
    1/4"-20
    19/64"7/16"15/32"SAE Grade 2
    5090455A16000000
    5/16"-18
    23/64"1/2"17/32"SAE Grade 2
    2590455A17000000
    3/8"-16
    27/64"9/16"5/8"SAE Grade 2
    2590455A18000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 2
    590455A15000000
     

    Sealing Cap Nuts

    Keep liquid, gas, debris, and other contaminants from seeping into or out of machinery, with no need for a separate O-ring. These nuts are often used outdoors to protect enclosures and other equipment from harsh weather. They also withstand high pressure, so they are useful for sealing pneumatic pumps and pressure valves. Also known as acorn nuts, they conceal protruding screw threads while fastening parts together and have a smooth, rounded head for a finished look.
    Stainless Steel
    Image of Product. Bottom orientation. Cap Nuts. Sealing Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Seal Material
    Seal Temp.
    Range, ° F
    Max. Pressure,
    psi
    Each
    18-8 Stainless Steel
    8-32
    5/32"5/16"5/16"Silicone Rubber-80 to 4001,20090194A11000000
    10-32
    3/16"3/8"25/64"Silicone Rubber-80 to 4001,20090194A1200000
    1/4"-20
    1/4"7/16"15/32"Silicone Rubber-80 to 4001,20090194A1300000
    3/8"-16
    3/8"5/8"5/8"Silicone Rubber-80 to 4001,20090194A1400000
    1/2"-13
    1/2"3/4"13/16"Silicone Rubber-80 to 4001,20090194A1500000
     

    High-Profile Cap Nuts

    Three times the thread depth of standard cap nuts, these cover and protect extra-long, protruding screws, so you don't have to cut them when fastening parts together. They help prevent damage to surrounding materials and reduce injuries. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    Image of Product. Front orientation. Cap Nuts. High-Profile Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Each
    18-8 Stainless Steel
    3/8"-16
    3/4"9/16"1 1/16"90023A101000000
    3/8"-16
    1"9/16"1 5/16"90023A10200000
    3/8"-16
    1 1/4"9/16"1 9/16"90023A10300000
    1/2"-13
    1"3/4"1 7/16"90023A10400000
    1/2"-13
    1 1/4"3/4"1 3/4"90023A10500000
    1/2"-13
    1 1/2"3/4"2"90023A10600000
     

    High-Heavy-Profile Cap Nuts

    20% wider and taller than standard cap nuts, these have high, flat sides so your wrench won't slip off as you tighten. They cover screws to protect the threads and to prevent damage to surrounding materials. Also known as acorn nuts, they have a smooth, rounded head to create a finished look.
    Stainless Steel
    Image of Product. Bottom orientation. Cap Nuts. High-Heavy-Profile Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Each
    18-8 Stainless Steel
    1/4"-20
    3/8"5/8"5/8"92040A10900000
    5/16"-18
    3/8"5/8"5/8"92040A1100000
    3/8"-16
    15/32"3/4"3/4"92040A1200000
    1/2"-13
    19/32"7/8"15/16"92040A13000000
    5/8"-11
    25/32"1 1/16"1 3/16"92040A14000000
    3/4"-10
    29/32"1 1/4"1 3/8"92040A15000000
    7/8"-9
    1 1/16"1 7/16"1 5/8"92040A16000000
     
    Steel
    Image of Product. Bottom orientation. Cap Nuts. High-Heavy-Profile Cap Nuts.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating. They offer minimal corrosion resistance, so they're best for dry environments.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Each
    Black-Oxide Steel
    1/4"-20
    3/8"5/8"5/8"90790A17500000
    5/16"-18
    3/8"5/8"5/8"90790A1850000
    3/8"-16
    15/32"3/4"3/4"90790A2040000
    1/2"-13
    19/32"7/8"15/16"90790A2160000
    5/8"-11
    25/32"1 1/16"1 3/16"90790A2990000
    3/4"-10
    29/32"1 1/4"1 3/8"90790A41700000
    7/8"-9
    1 1/16"1 3/8"1 5/8"90790A41900000
     

    Sanitary Cap Nuts

    With extremely smooth sides and rounded edges, these nuts are free of crevices where bacteria can grow. Use them to cover and protect exposed threads while fastening parts together. Nuts are certified by EHEDG to meet sanitary design standards. They have a Buna-N seal on the base that keeps liquid, debris, and other contaminants off the threads. The seal is made with metal and chemical additives, so you can find it with a metal detector or X-ray machine if it falls into your line. Also known as acorn nuts, these have a domed head to create a finished look.
    Stainless Steel
    Image of Product. Front orientation. Cap Nuts. Sanitary Cap Nuts.
    Super-Corrosion-Resistant 316 Stainless Steel—Won't corrode from frequent washdowns and can stand up to the harshest cleaners and detergents.
    Thread Size
    Thread
    Dp.
    Wd.
    Ht.
    Seal
    Material
    Certification
    Food Industry Std.
    Each
    Super-Corrosion-Resistant 316 Stainless Steel
    1/4"-20
    1/4"7/16"21/64"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A16000000
    5/16"-18
    9/32"1/2"25/64"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A1700000
    3/8"-16
    5/16"9/16"15/32"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A18000000
    7/16"-14
    21/64"11/16"33/64"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A19000000
    1/2"-13
    11/32"3/4"35/64"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A20000000
    5/8"-11
    7/16"15/16"43/64"Buna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A21000000
    M6 × 1 mm5.5 mm10 mm8 mmBuna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A11000000
    M8 × 1.25 mm6.5 mm13 mm10 mmBuna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A12000000
    M10 × 1.5 mm8 mm16 mm12 mmBuna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A13000000
    M12 × 1.75 mm9 mm18 mm14 mmBuna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A14000000
    M16 × 2 mm10.5 mm24 mm17 mmBuna-NEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    97511A15000000
     

    High-Profile Sanitary Cap Nuts

    Cover and protect 4" of exposed threads in food plants and other sanitary environments with these extra-long cap nuts. They are free of crevices where bacteria can grow and have a Buna-N seal on the base to keep liquid, debris, and other contaminants off the threads. The seal is made with metal and chemical additives, so you can find it with a metal detector or X-ray machine if it falls into your line. Nuts have a smooth, rounded head to create a finished look.
    Stainless Steel
    Image of Product. Bottom orientation. Cap Nuts. High-Profile Sanitary Cap Nuts.
    304 Stainless Steel—Won't corrode from frequent washdowns and can stand up to most cleaners and detergents.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Seal
    Material
    Food Industry Std.
    Each
    304 Stainless Steel
    5/8"-11
    29/32"7/8"4 5/32"Buna-NFDA Compliant 21 CFR 177.2600
    97513A101000000
    3/4"-10
    29/32"1"4 5/32"Buna-NFDA Compliant 21 CFR 177.2600
    97513A10200000
     

    Open-End Cap Nuts

    The open top allows threads to stick out slightly, so you don't have to worry about picking the wrong thread depth. These nuts also engage more threads than standard nuts for a tighter hold. The smooth, curved head creates a finished look, while still partially concealing and protecting the sides of the screw from damage.
    Stainless Steel
    Image of Product. Front orientation. Cap Nuts. Open-End Cap Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Each
    18-8 Stainless Steel
    4-40
    1/4"5/16"1/4"94301A10500000
    6-32
    1/4"5/16"1/4"94301A1100000
    8-32
    1/4"3/8"1/4"94301A1150000
    10-24
    5/16"7/16"5/16"94301A1200000
    10-32
    5/16"7/16"5/16"94301A1250000
    1/4"-20
    5/16"1/2"5/16"94301A1300000
    5/16"-18
    5/16"9/16"5/16"94301A1350000
    3/8"-16
    3/8"11/16"3/8"94301A1400000
    1/2"-13
    1/2"3/4"1/2"94301A1600000
     
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