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    338 Products

    Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    0-80
    1/16"3/16"3/16"__100000000000000
    1-72
    1/16"3/16"3/16"__10000000000000
    2-56
    5/64"3/16"3/16"__10000000000000
    3-48
    5/64"1/4"1/4"__10000000000000
    4-40
    5/32"1/4"1/4"__100000000000000
    4-48
    5/32"1/4"1/4"__1000000000000000
    5-40
    1/8"5/16"11/32"__10000000000000
    6-32
    5/32"5/16"11/32"__100000000000000
    6-32
    3/16"5/16"9/32"__100000000000000
    6-40
    5/32"5/16"11/32"__1000000000000000
    8-32
    5/32"5/16"11/32"__100000000000000
    8-32
    3/16"5/16"9/32"__100000000000000
    8-36
    5/32"5/16"11/32"__1000000000000000
    10-24
    3/16"3/8"13/32"__100000000000000
    10-24
    7/32"3/8"11/32"__1000000000000000
    10-32
    3/16"3/8"13/32"__100000000000000
    10-32
    7/32"3/8"11/32"__1000000000000000
    12-24
    7/32"3/8"13/32"__100000000000000
    12-28
    7/32"3/8"13/32"__10000000000000
    1/4"-20
    7/32"7/16"3/8"__1000000000000000
    1/4"-20
    1/4"7/16"15/32"__1000000000000000
    1/4"-20
    5/16"7/16"19/32"__1000000000000000
    1/4"-28
    7/32"7/16"3/8"__1000000000000000
    1/4"-28
    1/4"7/16"15/32"__1000000000000000
    5/16"-18
    9/32"9/16"7/16"__500000000000000
    5/16"-18
    5/16"1/2"17/32"__1000000000000000
    5/16"-24
    9/32"9/16"7/16"__500000000000000
    5/16"-24
    5/16"1/2"17/32"__1000000000000000
    3/8"-16
    5/16"5/8"1/2"__500000000000000
    3/8"-16
    3/8"9/16"5/8"__500000000000000
    3/8"-24
    5/16"5/8"1/2"__500000000000000
    3/8"-24
    3/8"9/16"5/8"__500000000000000
    7/16"-14
    3/8"3/4"9/16"__10000000000000
    7/16"-14
    7/16"5/8"11/16"__10000000000000
    7/16"-20
    3/8"3/4"9/16"__10000000000000
    7/16"-20
    7/16"5/8"11/16"__10000000000000
    1/2"-13
    3/8"3/4"9/16"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__10000000000000
    1/2"-20
    3/8"3/4"9/16"__10000000000000
    1/2"-20
    1/2"3/4"13/16"__10000000000000
    9/16"-12
    9/16"7/8"15/16"__100000000000000
    9/16"-18
    9/16"7/8"15/16"__100000000000000
    5/8"-11
    7/16"15/16"3/4"__100000000000000
    5/8"-11
    5/8"15/16"1"__100000000000000
    5/8"-18
    5/8"15/16"1"__100000000000000
    3/4"-10
    1/2"1 1/16"7/8"__100000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"__100000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"__100000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"__100000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"__100000000000000
    1"-8
    1"1 7/16"1 35/64"__100000000000000
    1"-14
    1"1 7/16"1 33/64"__100000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"__100000000000000
    M3 × 0.5 mm3.8 mm5.5 mm6 mmDIN 1587100000000000000
    M4 × 0.7 mm5.7 mm7 mm8 mmDIN 1587250000000000000
    M5 × 0.8 mm4.5 mm8 mm10 mmDIN 1587250000000000000
    M6 × 1 mm7.7 mm10 mm12 mmDIN 1587200000000000000
    M8 × 1.25 mm10.7 mm13 mm15 mmDIN 1587100000000000000
    M10 × 1.5 mm12.7 mm17 mm18 mmDIN 158750000000000000
    M12 × 1.75 mm15.7 mm19 mm22 mmDIN 158750000000000000
    M14 × 2 mm17.7 mm22 mm25 mmDIN 158710000000000000
    M16 × 2 mm20.6 mm24 mm28 mmDIN 158710000000000000
    M18 × 2.5 mm24.6 mm27 mm32 mmDIN 158710000000000000
    M20 × 2.5 mm25.6 mm30 mm34 mmDIN 158710000000000000
    M22 × 2.5 mm28.6 mm34 mm39 mmDIN 158710000000000000
    M24 × 3 mm30.5 mm36 mm42 mmDIN 158710000000000000
     
    Black-Oxide 18-8 Stainless Steel
    6-32
    5/32"5/16"11/32"__1000000000000000
    8-32
    5/32"5/16"11/32"__1000000000000000
    10-24
    3/16"3/8"13/32"__1000000000000000
    10-32
    3/16"3/8"13/32"__1000000000000000
    1/4"-20
    1/4"7/16"15/32"__1000000000000000
    5/16"-18
    5/16"1/2"17/32"__500000000000000
    3/8"-16
    3/8"9/16"5/8"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__10000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    2-56
    5/64"3/16"3/16"__100000000000000
    4-40
    5/32"1/4"1/4"__500000000000000
    5-40
    1/8"5/16"11/32"__10000000000000
    6-32
    5/32"5/16"11/32"__500000000000000
    8-32
    5/32"5/16"11/32"__500000000000000
    10-24
    3/16"3/8"13/32"__500000000000000
    10-32
    3/16"3/8"13/32"__500000000000000
    12-24
    7/32"3/8"13/32"__10000000000000
    1/4"-20
    1/4"7/16"15/32"__10000000000000
    1/4"-28
    1/4"7/16"15/32"__10000000000000
    5/16"-18
    5/16"1/2"17/32"__10000000000000
    5/16"-24
    5/16"1/2"17/32"__10000000000000
    3/8"-16
    3/8"9/16"5/8"__10000000000000
    3/8"-24
    3/8"9/16"5/8"__10000000000000
    7/16"-14
    7/16"5/8"11/16"__10000000000000
    7/16"-20
    7/16"5/8"11/16"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__10000000000000
    1/2"-20
    1/2"3/4"13/16"__10000000000000
    9/16"-12
    9/16"7/8"15/16"__100000000000000
    9/16"-18
    9/16"7/8"15/16"__100000000000000
    5/8"-11
    5/8"15/16"1"__100000000000000
    5/8"-18
    5/8"15/16"1"__100000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"__100000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"__100000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"__100000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"__100000000000000
    1"-8
    1"1 7/16"1 35/64"__100000000000000
    1"-12
    1"1 7/16"1 35/64"__100000000000000
    1"-14
    1"1 7/16"1 35/64"__100000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"__100000000000000
    1 1/4"-12
    1 1/4"1 13/16"1 61/64"__100000000000000
    M3 × 0.5 mm3.8 mm5.5 mm6 mmDIN 1587250000000000000
    M4 × 0.7 mm5.5 mm7 mm8 mmDIN 1587250000000000000
    M5 × 0.8 mm4.5 mm8 mm10 mmDIN 1587250000000000000
    M6 × 1 mm8 mm10 mm12 mmDIN 15872500000000000000
    M8 × 1.25 mm11 mm13 mm15 mmDIN 1587100000000000000
    M10 × 1.5 mm13 mm17 mm18 mmDIN 15871000000000000000
    M12 × 1.75 mm16 mm19 mm22 mmDIN 1587500000000000000
    M14 × 2 mm18 mm22 mm25 mmDIN 158710000000000000
    M16 × 2 mm21 mm24 mm28 mmDIN 158710000000000000
    M20 × 2.5 mm26 mm30 mm34 mmDIN 1587100000000000000
    M22 × 2.5 mm29 mm34 mm39 mmDIN 1587100000000000000
    M24 × 3 mm31 mm36 mm42 mmDIN 1587100000000000000
     
    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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    5/32"1/4"1/4"__2500000000000000
    3-48
    5/32"1/4"1/4"__100000000000000
    4-40
    5/32"1/4"1/4"__5000000000000000
    4-48
    5/32"1/4"1/4"__100000000000000
    5-40
    5/32"5/16"11/32"__100000000000000
    6-32
    5/32"5/16"11/32"__5000000000000000
    6-40
    5/32"5/16"11/32"__100000000000000
    8-32
    5/32"5/16"11/32"__5000000000000000
    8-36
    5/32"5/16"11/32"__100000000000000
    10-24
    3/16"3/8"13/32"__5000000000000000
    10-32
    3/16"3/8"13/32"__5000000000000000
    1/4"-20
    1/4"7/16"15/32"__2500000000000000
    1/4"-28
    1/4"7/16"15/32"__2500000000000000
    5/16"-18
    5/16"1/2"17/32"__2500000000000000
    5/16"-24
    5/16"1/2"17/32"__2500000000000000
    3/8"-16
    3/8"9/16"5/8"__2500000000000000
    3/8"-24
    3/8"9/16"5/8"__2500000000000000
    7/16"-14
    7/16"5/8"11/16"__2000000000000000
    7/16"-20
    7/16"5/8"11/16"__2000000000000000
    1/2"-13
    1/2"3/4"13/16"__1000000000000000
    1/2"-20
    1/2"3/4"13/16"__1000000000000000
    5/8"-11
    5/8"15/16"1"__500000000000000
    5/8"-18
    5/8"15/16"1"__500000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"__10000000000000
    3/4"-16
    3/4"1 1/16"1 5/32"__10000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"__10000000000000
    7/8"-14
    7/8"1 1/4"1 23/64"__10000000000000
    1"-8
    1"1 7/16"1 35/64"__10000000000000
    1"-14
    1"1 7/16"1 35/64"__10000000000000
    1 1/4"-7
    1 1/4"1 13/16"1 61/64"__100000000000000
    1 1/4"-12
    1 1/4"1 13/16"1 61/64"__100000000000000
    M4 × 0.7 mm5.3 mm7 mm8 mmDIN 15875000000000000000
    M5 × 0.8 mm3.7 mm8 mm10 mmDIN 15875000000000000000
    M6 × 1 mm7.7 mm10 mm12 mmDIN 15875000000000000000
    M8 × 1.25 mm10.7 mm13 mm15 mmDIN 15872500000000000000
    M10 × 1.5 mm12.7 mm17 mm18 mmDIN 1587100000000000000
    M12 × 1.75 mm15.7 mm19 mm22 mmDIN 15871000000000000000
     
    Black Corrosion-Resistant-Coated Steel
    4-40
    5/32"1/4"1/4"__1000000000000000
    6-32
    5/32"5/16"11/32"__1000000000000000
    8-32
    5/32"5/16"11/32"__1000000000000000
    10-24
    3/16"3/8"13/32"__50000000000000
    10-32
    3/16"3/8"13/32"__50000000000000
    1/4"-20
    1/4"7/16"15/32"__50000000000000
    5/16"-18
    5/16"1/2"17/32"__500000000000000
    3/8"-16
    3/8"9/16"5/8"__10000000000000
    7/16"-14
    7/16"5/8"11/16"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__10000000000000
    9/16"-12
    9/16"7/8"15/16"__10000000000000
    5/8"-11
    5/8"15/16"1"__10000000000000
     
    Nickel-Plated Steel
    6-32
    5/32"5/16"1/4"__10000000000000000
    8-32
    5/32"5/16"1/4"__10000000000000000
    10-24
    3/16"3/8"5/16"__1000000000000000
    10-32
    3/16"3/8"5/16"__10000000000000000
    1/4"-20
    1/4"7/16"3/8"__10000000000000000
    5/16"-18
    5/16"9/16"15/32"__5000000000000000
    3/8"-16
    3/8"5/8"1/2"__250000000000000
    1/2"-13
    1/2"3/4"9/16"__2500000000000000
    5/8"-11
    5/8"15/16"13/16"__1000000000000000
    3/4"-10
    3/4"1 1/8"1 1/8"__10000000000000
     
    Chrome-Plated Steel
    M4 × 0.7 mm3.9 mm7 mm8 mmDIN 1587500000000000000
    M5 × 0.8 mm5.6 mm8 mm10 mmDIN 1587500000000000000
    M6 × 1 mm5.7 mm10 mm12 mmDIN 1587500000000000000
    M8 × 1.25 mm8.2 mm13 mm15 mmDIN 158710000000000000
    M10 × 1.5 mm9.7 mm17 mm18 mmDIN 158710000000000000
    M12 × 1.75 mm12.2 mm19 mm22 mmDIN 158710000000000000
     
    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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 5
    1000000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 5
    1000000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 5
    1000000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 5
    500000000000000
    5/8"-11
    5/8"15/16"1"SAE Grade 5
    10000000000000
    3/4"-10
    3/4"1 1/8"1 5/32"SAE Grade 5
    10000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"SAE Grade 5
    100000000000000
    1"-8
    1"1 7/16"1 35/64"SAE Grade 5
    100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 5
    10000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 5
    10000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 5
    10000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 5
    100000000000000
     
    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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 8
    __10000000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 8
    __1000000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 8
    __1000000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 8
    __10000000000000
    5/8"-11
    5/8"15/16"1"SAE Grade 8
    __10000000000000
    3/4"-10
    3/4"1 1/8"1 5/32"SAE Grade 8
    __10000000000000
    7/8"-9
    7/8"1 1/4"1 23/64"SAE Grade 8
    __100000000000000
    1"-8
    1"1 7/16"1 35/64"SAE Grade 8
    __100000000000000
    M6 × 1 mm5.7 mm10 mm12 mmISO Class 10
    DIN 1587500000000000000
    M8 × 1.25 mm8.2 mm13 mm15 mmISO Class 10
    DIN 1587500000000000000
    M10 × 1.5 mm9.7 mm17 mm18 mmISO Class 10
    DIN 158710000000000000
    M12 × 1.75 mm12.2 mm19 mm22 mmISO Class 10
    DIN 1587100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/4"7/16"15/32"SAE Grade 8
    __10000000000000
    5/16"-18
    5/16"1/2"17/32"SAE Grade 8
    __10000000000000
    3/8"-16
    3/8"9/16"5/8"SAE Grade 8
    __10000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 8
    __100000000000000
     

    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"-16200Plastic Box000000000000000
     
    18-8 Stainless Steel
    6-32, 8-32, 10-32, 1/4"-20, 5/16"-18, 3/8"-16200Plastic Box000000000000000
     

    Nylon-Insert Cap Nuts
    3D CAD models available

    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. Front 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
    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 98624550000000000000000
    M5 × 0.8 mm3.5 mm8 mm10.5 mmISO Class 6
    DIN 986245250000000000000
    M6 × 1 mm3.9 mm10 mm12 mmISO Class 6
    DIN 986245250000000000000
    M8 × 1.25 mm5.2 mm13 mm14 mmISO Class 6
    DIN 9862452500000000000000
    M10 × 1.5 mm6.4 mm16 mm18 mmISO Class 6
    DIN 986245100000000000000
    M12 × 1.75 mm8.3 mm18 mm23 mmISO Class 6
    DIN 98624550000000000000
    M16 × 2 mm11.3 mm24 mm28 mmISO Class 6
    DIN 98624510000000000000
    M20 × 2.5 mm13.5 mm30 mm35 mmISO Class 6
    DIN 98624510000000000000
     
    Zinc-Plated Steel with Nylon 6/6 Cap
    8-32
    9/64"11/32"23/64"SAE Grade 2
    __250250000000000000
    10-24
    9/64"3/8"23/64"SAE Grade 2
    __250250000000000000
    10-32
    9/64"3/8"23/64"SAE Grade 2
    __250250000000000000
    1/4"-20
    7/32"7/16"31/64"SAE Grade 2
    __250250000000000000
    5/16"-18
    1/4"1/2"1/2"SAE Grade 2
    __250100000000000000
    3/8"-16
    21/64"9/16"5/8"SAE Grade 2
    __2502500000000000000
     
    Steel with Nylon 6/6 Cap
    8-32
    9/64"11/32"23/64"SAE Grade 2
    __250250000000000000
    10-32
    9/64"3/8"23/64"SAE Grade 2
    __250250000000000000
    1/4"-20
    7/32"7/16"31/64"SAE Grade 2
    __250250000000000000
    1/4"-28
    7/32"7/16"31/64"SAE Grade 2
    __250250000000000000
    5/16"-24
    1/4"1/2"1/2"SAE Grade 2
    __250250000000000000
    3/8"-24
    21/64"9/16"5/8"SAE Grade 2
    __2502500000000000000
     
    Medium-Strength Steel
    Image of Product. Front 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
    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
    25010000000000000000
     

    Threadlocker Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Contains Annotated, Border. Cap Nuts. Threadlocker 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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-24
    3/16"3/8"13/32"__5000000000000000
    10-32
    3/16"3/8"13/32"__500000000000000
    12-24
    7/32"3/8"13/32"__500000000000000
    1/4"-20
    1/4"7/16"15/32"__500000000000000
    1/4"-28
    1/4"7/16"15/32"__500000000000000
    5/16"-18
    19/64"1/2"17/32"__500000000000000
    3/8"-16
    3/8"9/16"5/8"__500000000000000
    3/8"-24
    3/8"9/16"5/8"__500000000000000
    7/16"-14
    7/16"5/8"45/64"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__10000000000000
    5/8"-11
    5/8"15/16"1"__100000000000000
    3/4"-10
    3/4"1 1/16"1 5/32"__100000000000000
    M5 × 0.8 mm5.6 mm8 mm10 mmDIN 1587500000000000000
    M6 × 1 mm5.7 mm10 mm12 mmDIN 1587500000000000000
    M8 × 1.25 mm8.2 mm13 mm15 mmDIN 1587500000000000000
    M10 × 1.5 mm9.7 mm17 mm18 mmDIN 1587100000000000000
    M12 × 1.75 mm12.2 mm19 mm22 mmDIN 1587100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-32
    3/16"3/8"13/32"__500000000000000
    1/4"-20
    1/4"7/16"15/32"__500000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    10-24
    3/16"3/8"13/32"__500000000000000
    10-32
    3/16"3/8"13/32"__500000000000000
    1/4"-20
    1/4"7/16"15/32"__500000000000000
    5/16"-18
    5/16"1/2"17/32"__10000000000000
    3/8"-16
    3/8"9/16"5/8"__10000000000000
    1/2"-13
    1/2"3/4"13/16"__100000000000000
    5/8"-11
    5/8"15/16"1"__100000000000000
     

    Distorted-Thread Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    4-40
    5/32"1/4"1/4"10000000000000000
    6-32
    5/32"5/16"11/32"1000000000000000
    8-32
    5/32"5/16"11/32"1000000000000000
    10-24
    3/16"3/8"13/32"1000000000000000
    10-32
    3/16"3/8"13/32"1000000000000000
    1/4"-20
    1/4"7/16"15/32"1000000000000000
    1/4"-28
    1/4"7/16"15/32"1000000000000000
    5/16"-18
    5/16"1/2"17/32"500000000000000
    5/16"-24
    5/16"1/2"17/32"500000000000000
    3/8"-16
    3/8"9/16"5/8"500000000000000
    3/8"-24
    3/8"9/16"5/8"500000000000000
    7/16"-14
    7/16"5/8"11/16"10000000000000
    7/16"-20
    7/16"5/8"11/16"10000000000000
    1/2"-13
    1/2"3/4"13/16"100000000000000
    1/2"-20
    1/2"3/4"13/16"100000000000000
    5/8"-11
    19/32"1"63/64"10000000000000
    3/4"-10
    11/16"1 1/16"1 3/16"10000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    8-32
    5/32"5/16"11/32"10000000000000
    10-24
    3/16"3/8"13/32"10000000000000
    10-32
    3/16"3/8"13/32"10000000000000
    1/4"-20
    1/4"7/16"15/32"10000000000000
    5/16"-18
    5/16"1/2"17/32"10000000000000
    3/8"-16
    3/8"9/16"5/8"10000000000000
    1/2"-13
    1/2"3/4"13/16"100000000000000
     
    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
    Dp.
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    6-32
    5/32"5/16"11/32"SAE Grade 2
    50000000000000000
    8-32
    5/32"5/16"11/32"SAE Grade 2
    5000000000000000
    10-24
    3/16"3/8"13/32"SAE Grade 2
    2500000000000000
    10-32
    3/16"3/8"13/32"SAE Grade 2
    2500000000000000
    1/4"-20
    19/64"7/16"15/32"SAE Grade 2
    5000000000000000
    5/16"-18
    23/64"1/2"17/32"SAE Grade 2
    2500000000000000
    3/8"-16
    27/64"9/16"5/8"SAE Grade 2
    2500000000000000
    1/2"-13
    1/2"3/4"13/16"SAE Grade 2
    500000000000000
     

    Sealing Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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
    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 4001,20000000000000000
    10-32
    3/16"3/8"25/64"Silicone Rubber-80 to 4001,2000000000000000
    1/4"-20
    1/4"7/16"15/32"Silicone Rubber-80 to 4001,2000000000000000
    3/8"-16
    3/8"5/8"5/8"Silicone Rubber-80 to 4001,2000000000000000
    1/2"-13
    1/2"3/4"13/16"Silicone Rubber-80 to 4001,2000000000000000
     

    High-Profile Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    3/8"-16
    3/4"9/16"1 1/16"1000000000000000
    3/8"-16
    1"9/16"1 5/16"100000000000000
    3/8"-16
    1 1/4"9/16"1 9/16"100000000000000
    1/2"-13
    1"3/4"1 7/16"100000000000000
    1/2"-13
    1 1/4"3/4"1 3/4"100000000000000
    1/2"-13
    1 1/2"3/4"2"100000000000000
     

    High-Heavy-Profile Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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
    Dp.
    Wd.
    Ht.
    Each
    18-8 Stainless Steel
    1/4"-20
    3/8"5/8"5/8"00000000000000
    5/16"-18
    3/8"5/8"5/8"0000000000000
    3/8"-16
    15/32"3/4"3/4"0000000000000
    1/2"-13
    19/32"7/8"15/16"00000000000000