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    290 Products

    Thin-Profile Nylon-Insert Locknuts
    3D CAD models available

    About half the height of standard-profile locknuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Zinc Yellow-Chromate-Plated Steel—With a more durable finish than clear zinc plating, these nuts are suitable for most wet and outdoor environments. However, they won't hold up to the harsh chemicals that stainless steel can.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc Yellow-Chromate-Plated Steel
    1/4"-20
    7/16"13/64"SAE Grade 8
    Not Rated10000000000000000
    1/4"-28
    7/16"13/64"SAE Grade 8
    250100000000000000
    5/16"-18
    1/2"1/4"SAE Grade 8
    Not Rated10000000000000000
    5/16"-24
    1/2"1/4"SAE Grade 8
    2501000000000000000
    3/8"-16
    9/16"17/64"SAE Grade 8
    Not Rated10000000000000000
    3/8"-24
    9/16"17/64"SAE Grade 8
    Not Rated5000000000000000
    7/16"-14
    5/8"5/16"SAE Grade 8
    Not Rated250000000000000
    7/16"-20
    5/8"5/16"SAE Grade 8
    Not Rated250000000000000
    1/2"-13
    3/4"5/16"SAE Grade 8
    Not Rated2500000000000000
    1/2"-20
    3/4"5/16"SAE Grade 8
    25050000000000000
    5/8"-11
    15/16"25/64"SAE Grade 8
    Not Rated100000000000000
    5/8"-18
    15/16"25/64"SAE Grade 8
    25050000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    25010000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    25010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 8
    25010000000000000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 8
    Not Rated100000000000000
    1 1/2"-12
    2 3/16"51/64"SAE Grade 8
    Not Rated100000000000000
     
    Zinc-Plated Steel
    5/16"-24
    1/2"1/4"SAE Grade 8
    2201000000000000000
    1/2"-20
    3/4"5/16"SAE Grade 8
    22050000000000000
    5/8"-18
    15/16"25/64"SAE Grade 8
    220500000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    22010000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    22010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 8
    22010000000000000
    1 1/8"-12
    1 53/64"41/64"SAE Grade 8
    220100000000000000
     
    Black-Oxide Steel
    1/4"-20
    7/16"13/64"SAE Grade 8
    2502500000000000000
    1/4"-28
    7/16"13/64"SAE Grade 8
    2501000000000000000
    5/16"-18
    1/2"1/4"SAE Grade 8
    2502500000000000000
    5/16"-24
    1/2"1/4"SAE Grade 8
    2501000000000000000
    3/8"-16
    9/16"17/64"SAE Grade 8
    250100000000000000
    3/8"-24
    9/16"17/64"SAE Grade 8
    250100000000000000
    7/16"-20
    5/8"5/16"SAE Grade 8
    2501000000000000000
    1/2"-13
    3/4"5/16"SAE Grade 8
    2501000000000000000
    1/2"-20
    3/4"5/16"SAE Grade 8
    25050000000000000
    5/8"-11
    15/16"25/64"SAE Grade 8
    250500000000000000
    5/8"-18
    15/16"25/64"SAE Grade 8
    25050000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 8
    25010000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 8
    25010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 8
    25010000000000000
    1 1/4"-12
    1 13/16"47/64"SAE Grade 8
    250100000000000000
    1 1/2"-12
    2 11/64"51/64"SAE Grade 8
    250100000000000000
     
    Medium-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    These Grade 5 or Class 8 nuts are your go-to for fastening 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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    5/8"-11
    15/16"25/64"SAE Grade 5
    2205000000000000000
    5/8"-18
    15/16"25/64"SAE Grade 5
    220500000000000000
    3/4"-10
    1 1/16"13/32"SAE Grade 5
    220500000000000000
    3/4"-16
    1 1/16"13/32"SAE Grade 5
    2201000000000000000
    7/8"-14
    1 1/4"15/32"SAE Grade 5
    22010000000000000
    1"-8
    1 7/16"35/64"SAE Grade 5
    22010000000000000
    1"-14
    1 7/16"35/64"SAE Grade 5
    22010000000000000
    1 1/8"-7
    1 5/8"41/64"SAE Grade 5
    220100000000000000
    1 1/4"-7
    1 13/16"3/4"SAE Grade 5
    220100000000000000
    1 1/4"-12
    1 13/16"3/4"SAE Grade 5
    220100000000000000
    1 1/2"-6
    2 3/16"51/64"SAE Grade 5
    220100000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    Rated Grade 2, Class 6, or lower, these locknuts 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.
    Black Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Black Corrosion-Resistant-Coated Steel—These nuts combine 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
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    2-56
    1/4"7/64"220__100000000000000000
    4-40
    1/4"7/64"220__1000000000000000
    5-40
    1/4"7/64"220__1000000000000000
    6-32
    5/16"1/8"220__10000000000000000
    8-32
    11/32"11/64"220__1000000000000000
    10-24
    3/8"11/64"220__1000000000000000
    10-32
    3/8"11/64"220__1000000000000000
    12-24
    7/16"13/64"220__1000000000000000
    1/4"-20
    7/16"13/64"220__1000000000000000
    1/4"-28
    7/16"13/64"220__1000000000000000
    5/16"-18
    1/2"1/4"220__1000000000000000
    5/16"-24
    1/2"1/4"220__1000000000000000
    3/8"-16
    9/16"17/64"220__1000000000000000
    3/8"-24
    9/16"17/64"220__1000000000000000
    7/16"-14
    5/8"5/16"220__1000000000000000
    7/16"-20
    5/8"5/16"220__10000000000000000
    1/2"-13
    3/4"5/16"220__10000000000000000
    1/2"-20
    3/4"5/16"220__10000000000000000
    9/16"-12
    7/8"23/64"220__10000000000000000
    9/16"-18
    7/8"23/64"220__10000000000000000
    5/8"-11
    15/16"25/64"220__5000000000000000
    5/8"-18
    15/16"25/64"220__5000000000000000
    3/4"-10
    1 1/16"13/32"220__100000000000000
    3/4"-16
    1 1/16"13/32"220__100000000000000
    7/8"-9
    1 1/4"15/32"220__50000000000000
    7/8"-14
    1 1/4"15/32"220__50000000000000
    1"-8
    1 7/16"35/64"220__10000000000000
    1"-14
    1 7/16"35/64"220__10000000000000
    1 1/8"-7
    1 5/8"41/64"220__10000000000000
    1 1/4"-7
    1 13/16"3/4"220__10000000000000
    1 1/4"-12
    1 13/16"3/4"220__10000000000000
    1 3/8"-6
    2"51/64"220__10000000000000
    1 1/2"-6
    2 3/16"51/64"220__10000000000000
    M3 × 0.5 mm5.5 mm3.9 mm245ISO 10511250000000000000
    M4 × 0.7 mm7 mm5 mm245ISO 10511250000000000000
    M5 × 0.8 mm8 mm5 mm245ISO 10511250000000000000
    M6 × 1 mm10 mm6 mm245ISO 10511100000000000000
    M8 × 1.25 mm13 mm6.8 mm245ISO 1051150000000000000
    M10 × 1.5 mm16 mm8.6 mm245ISO 1051150000000000000
    M12 × 1.75 mm18 mm10.3 mm245ISO 1051150000000000000
    M14 × 2 mm21 mm11.4 mm245ISO 1051150000000000000
    M16 × 2 mm24 mm12.5 mm245ISO 1051110000000000000
    M18 × 2.5 mm26 mm13 mm245ISO 1051110000000000000
    M20 × 2.5 mm30 mm14.9 mm245ISO 1051110000000000000
    M24 × 3 mm36 mm17.8 mm245ISO 10511100000000000000
     
    Black Zinc-Plated Steel
    6-32
    5/16"1/8"220__250000000000000
    8-32
    11/32"11/64"220__250000000000000
    10-24
    3/8"11/64"220__250000000000000
    10-32
    3/8"11/64"220__250000000000000
    12-24
    7/16"13/64"220__250000000000000
    1/4"-20
    7/16"13/64"220__250000000000000
    5/16"-18
    1/2"1/4"220__100000000000000
    3/8"-16
    9/16"17/64"220__100000000000000
     
    Black Corrosion-Resistant-Coated Steel
    6-32
    5/16"1/8"220__50000000000000
    8-32
    11/32"11/64"220__50000000000000
    10-24
    3/8"11/64"220__50000000000000
    10-32
    3/8"11/64"220__50000000000000
    1/4"-20
    7/16"13/64"220__50000000000000
    5/16"-18
    1/2"1/4"220__50000000000000
    3/8"-16
    9/16"17/64"220__50000000000000
    1/2"-13
    3/4"5/16"220__50000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts 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 to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    4-40
    1/4"7/64"2205000000000000000
    6-32
    5/16"1/8"2201000000000000000
    8-32
    11/32"11/64"2201000000000000000
    10-24
    3/8"11/64"2201000000000000000
    10-32
    3/8"11/64"220500000000000000
    1/4"-20
    7/16"13/64"220500000000000000
    1/4"-28
    7/16"13/64"220500000000000000
    5/16"-18
    1/2"1/4"220500000000000000
    5/16"-24
    1/2"1/4"220500000000000000
    3/8"-16
    9/16"17/64"220250000000000000
    3/8"-24
    9/16"17/64"220250000000000000
    7/16"-14
    5/8"5/16"220100000000000000
    7/16"-20
    5/8"5/16"22050000000000000
    1/2"-13
    3/4"5/16"220100000000000000
    1/2"-20
    3/4"5/16"22050000000000000
    9/16"-18
    7/8"23/64"220100000000000000
    5/8"-11
    15/16"25/64"22010000000000000
    5/8"-18
    15/16"25/64"22010000000000000
    3/4"-10
    1 1/16"13/32"22010000000000000
    3/4"-16
    1 1/16"13/32"220100000000000000
    7/8"-9
    1 1/4"15/32"22010000000000000
    7/8"-14
    1 1/4"15/32"220100000000000000
    1"-8
    1 7/16"35/64"220100000000000000
    1"-14
    1 7/16"35/64"220100000000000000
    1 1/8"-7
    1 5/8"41/64"220100000000000000
    1 1/4"-7
    1 13/16"3/4"220100000000000000
    1 1/4"-12
    1 13/16"3/4"220100000000000000
    1 1/2"-6
    2 3/16"51/64"220100000000000000
     
    Black-Oxide 18-8 Stainless Steel
    4-40
    1/4"3/32"22010000000000000000
    6-32
    5/16"1/8"22010000000000000000
    8-32
    11/32"11/64"22010000000000000000
    10-24
    3/8"11/64"22010000000000000000
    10-32
    3/8"11/64"22010000000000000000
    1/4"-20
    7/16"13/64"2205000000000000000
    5/16"-18
    1/2"1/4"2205000000000000000
    3/8"-16
    9/16"17/64"2205000000000000000
    3/8"-24
    9/16"17/64"2205000000000000000
    1/2"-13
    3/4"5/16"22050000000000000
    1/2"-20
    3/4"5/16"22050000000000000
     
    316 Stainless Steel
    10-24
    3/8"11/64"2205000000000000000
    10-32
    3/8"11/64"2205000000000000000
    1/4"-20
    7/16"13/64"220250000000000000
    1/4"-28
    7/16"13/64"2205000000000000000
    5/16"-18
    1/2"1/4"220250000000000000
    5/16"-24
    1/2"1/4"2205000000000000000
    3/8"-16
    9/16"17/64"2202500000000000000
    3/8"-24
    9/16"17/64"2202500000000000000
    7/16"-14
    5/8"5/16"2202500000000000000
    7/16"-20
    5/8"5/16"2202500000000000000
    1/2"-13
    3/4"5/16"2201000000000000000
    1/2"-20
    3/4"5/16"2201000000000000000
    3/4"-10
    1 1/16"25/64"220100000000000000
     

    Thin-Heavy-Profile Nylon-Insert Locknuts
    3D CAD models available

    About half the height of standard-profile locknuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    High-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Black Phosphate-Coated Steel—The dark coating creates both a finished appearance and a barrier against rust that's comparable to zinc yellow-chromate plating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Each
    Black Phosphate-Coated Steel
    1 1/4"-12
    2"1 7/64"ASTM Grade C
    25000000000000000
    1 1/2"-12
    2 3/8"1 5/16"ASTM Grade C
    2500000000000000
    1 3/4"-12
    2 3/4"1 15/32"ASTM Grade C
    25000000000000000
    2"-12
    3 1/8"1 43/64"ASTM Grade C
    25000000000000000
    2 1/4"-12
    3 1/2"1 15/16"ASTM Grade C
    25000000000000000
    2 1/2"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    2 3/4"-12
    4"2 3/16"ASTM Grade C
    25000000000000000
    3"-12
    4 1/2"2 41/64"ASTM Grade C
    250000000000000000
     
    Steel
    1 1/8"-12
    1 7/8"1"ASTM Grade C
    25000000000000000
    1 3/8"-12
    2 13/64"1 3/16"ASTM Grade C
    25000000000000000
     
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    Rated Grade 2, Class 6, or lower, these locknuts 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.
    Black Corrosion-Resistant-Coated Steel—These nuts combine 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
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    1/2"9/32"250100000000000000000
    5/16"-18
    9/16"5/16"25010000000000000000
    3/8"-16
    11/16"13/32"2505000000000000000
    1/2"-13
    7/8"17/32"2502500000000000000
    5/8"-11
    1 1/16"39/64"2501000000000000000
    3/4"-10
    1 1/4"45/64"2501000000000000000
    1"-8
    1 5/8"57/64"25010000000000000
    1 1/4"-7
    2"1 7/64"25010000000000000
     
    Black Corrosion-Resistant-Coated Steel
    1/4"-20
    1/2"9/32"25050000000000000
    5/16"-18
    9/16"5/16"25050000000000000
    3/8"-16
    11/16"13/32"25010000000000000
    1/2"-13
    7/8"17/32"25010000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Nylon-Insert Locknuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    316 Stainless Steel—Our most corrosion-resistant nuts, these hold up in just about any environment. They won't degrade from exposure to weather, salt water, and most chemicals.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    1/4"-20
    1/2"9/32"25025000000000000000
    5/16"-18
    9/16"5/16"2502000000000000000
    3/8"-16
    11/16"13/32"2501000000000000000
    1/2"-13
    7/8"17/32"25010000000000000
    5/8"-11
    1 1/16"5/8"25010000000000000
    3/4"-10
    1 1/4"45/64"250100000000000000
    1"-8
    1 5/8"59/64"250100000000000000
     
    316 Stainless Steel
    3/8"-16
    11/16"13/32"25010000000000000
    1/2"-13
    7/8"17/32"25010000000000000
    5/8"-11
    1 1/16"39/64"25010000000000000
    3/4"-10
    1 1/4"45/64"250100000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts
    3D CAD models available

    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. They are about half the height of standard-profile locknuts to fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    Rated Grade 2, Class 6, or lower, these locknuts 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.
    Cadmium Yellow-Chromate-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Mil. Specs.
    Met
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    4-40
    1/4"1/8"MS21083N04250NASM2108310000000000000000
    6-32
    5/16"9/64"MS21083N06250NASM210831000000000000000
    8-32
    11/32"3/16"MS21083N08250NASM21083100000000000000
    10-32
    3/8"3/16"MS21083N3250NASM21083100000000000000
    1/4"-28
    7/16"7/32"MS21083N4250NASM21083100000000000000
    1/2"-20
    3/4"5/16"MS21083N8250NASM2108310000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Mil. Specs.
    Met
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    2-56
    1/4"7/64"MS21083C02250NASM210835000000000000000
    4-40
    1/4"1/8"MS21083C04250NASM210831000000000000000
    6-32
    5/16"9/64"MS21083C06250NASM210831000000000000000
    8-32
    11/32"3/16"MS21083C08250NASM2108350000000000000
    10-32
    3/8"3/16"MS21083C3250NASM21083500000000000000
    1/4"-28
    7/16"7/32"MS21083C4250NASM21083500000000000000
    5/16"-24
    1/2"17/64"MS21083C5250NASM2108310000000000000
    3/8"-24
    9/16"9/32"MS21083C6250NASM2108310000000000000
    7/16"-20
    11/16"21/64"MS21083C7250NASM21083100000000000000
    1/2"-20
    3/4"5/16"MS21083C8250NASM2108310000000000000
    5/8"-18
    15/16"13/32"MS21083C10250NASM21083100000000000000
     

    Thin-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    About two-thirds the height of standard flex-top nuts, these fit in spaces with low clearance. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    6-32
    5/16"9/64"25000000000000000
    8-32
    11/32"3/16"2500000000000000
    10-24
    3/8"3/16"2500000000000000
    10-32
    3/8"3/16"2500000000000000
    1/4"-20
    7/16"7/32"2500000000000000
    1/4"-28
    7/16"7/32"2500000000000000
    5/16"-18
    1/2"17/64"100000000000000
    5/16"-24
    1/2"17/64"1000000000000000
    3/8"-16
    9/16"9/32"1000000000000000
    3/8"-24
    9/16"9/32"1000000000000000
    7/16"-20
    5/8"21/64"500000000000000
    1/2"-13
    3/4"21/64"500000000000000
    1/2"-20
    3/4"21/64"500000000000000
    5/8"-11
    15/16"13/32"10000000000000
    5/8"-18
    15/16"13/32"10000000000000
    3/4"-10
    1 1/16"27/64"10000000000000
    3/4"-16
    1 1/16"27/64"10000000000000
    7/8"-9
    1 1/4"31/64"100000000000000
    1"-8
    1 7/16"37/64"100000000000000
    1"-14
    1 7/16"37/64"100000000000000
    1 1/4"-12
    1 13/16"49/64"100000000000000
    1 1/2"-12
    2 3/16"57/64"100000000000000
     
    Steel
    6-32
    5/16"9/64"100000000000000
    8-32
    11/32"3/16"100000000000000
    10-24
    3/8"3/16"100000000000000
    10-32
    3/8"3/16"100000000000000
    1/4"-20
    7/16"7/32"100000000000000
    1/4"-28
    7/16"7/32"100000000000000
    5/16"-18
    1/2"17/64"50000000000000
    5/16"-24
    1/2"17/64"50000000000000
    3/8"-16
    9/16"9/32"50000000000000
    3/8"-24
    9/16"9/32"50000000000000
    1/2"-13
    3/4"21/64"10000000000000
    1/2"-20
    3/4"21/64"10000000000000
    5/8"-11
    15/16"13/32"10000000000000
    5/8"-18
    15/16"13/32"10000000000000
    3/4"-10
    1 1/16"27/64"10000000000000
    3/4"-16
    1 1/16"27/64"10000000000000
    1"-14
    1 7/16"37/64"10000000000000
    1 1/8"-12
    1 5/8"41/64"100000000000000
    1 1/4"-12
    1 13/16"49/64"100000000000000
    1 3/8"-12
    1 15/16"53/64"100000000000000
    1 1/2"-12
    2 3/16"57/64"100000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Locknuts. Thin-Profile Flex-Top Locknuts for Heavy Vibration.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    6-32
    5/16"9/64"10000000000000000
    8-32
    11/32"3/16"500000000000000
    10-24
    3/8"3/16"500000000000000
    10-32
    3/8"3/16"1000000000000000
    1/4"-20
    7/16"7/32"500000000000000
    1/4"-28
    7/16"7/32"500000000000000
    5/16"-18
    1/2"17/64"10000000000000
    5/16"-24
    1/2"17/64"10000000000000
    3/8"-16
    9/16"9/32"10000000000000
    3/8"-24
    9/16"9/32"10000000000000
    1/2"-13
    3/4"21/64"10000000000000
    1/2"-20
    3/4"21/64"100000000000000
    5/8"-18
    15/16"13/32"100000000000000
    3/4"-16
    1 1/16"27/64"100000000000000
    7/8"-14
    1 1/4"31/64"1000000000000000
     

    Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration
    3D CAD models available

    About two-thirds the height of standard flex-top nuts and 10% wider, these fit in spaces with low clearance and handle heavier loads by distributing them over a larger area. Because of the thin profile, you can also use them as jam nuts by threading them against a hex nut to hold it in place. The top section expands to grip the screw on all sides for a stronger hold than both nylon-insert and distorted-thread locknuts. As a result, they're suitable for use in equipment with constant, vigorous vibration, such as engines. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Steel
    Image of Product. Front orientation. Locknuts. Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration.
    These locknuts have equivalent strength to Grade 8 and Class 10 steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Cadmium-Plated Steel—These locknuts have good lubricity to thread on smoothly and ease installation. The plating also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Cadmium-Plated Steel
    1/4"-20
    1/2"7/32"25000000000000000
    5/16"-18
    9/16"17/64"100000000000000
    3/8"-16
    5/8"9/32"1000000000000000
    7/16"-14
    3/4"21/64"10000000000000
    1/2"-13
    13/16"21/64"500000000000000
    5/8"-11
    1"13/32"10000000000000
    3/4"-10
    1 1/8"27/64"100000000000000
    7/8"-9
    1 5/16"31/64"100000000000000
    1"-8
    1 1/2"37/64"100000000000000
     

    Thin-Profile Steel-Insert Locknuts for Extreme Vibration
    3D CAD models available

    About two-thirds the height of standard steel-insert locknuts, these fit in spaces with low clearance and offer the most secure hold of all our thin-profile locknuts. You can also use them as jam nuts by threading them against a hex nut to hold it in place. The tab on the insert stops the nut from rotating, even under extreme vibration. These locknuts are ideal for equipment with constant motion or jarring starts and stops, including conveyors, shakers, and compactors. You can even reuse them once or twice, but their holding power decreases with each use.
    High-Strength Steel
    Image of Product. Bottom orientation. Locknuts. Thin-Profile Steel-Insert Locknuts for Extreme Vibration.
    Rated Grade 8, Grade C, or Class 10, these locknuts are about 25% stronger than medium-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Each
    Steel
    1/2"-13
    3/4"13/32"SAE Grade 8
    00000000000000
    5/8"-11
    15/16"1/2"SAE Grade 8
    0000000000000
    3/4"-10
    1 1/8"9/16"SAE Grade 8
    0000000000000
    3/4"-16
    1 1/8"9/16"SAE Grade 8
    00000000000000
    7/8"-9
    1 5/16"21/32"SAE Grade 8
    00000000000000
    7/8"-14
    1 5/16"19/32"SAE Grade 8
    00000000000000
    1"-8
    1 1/2"3/4"SAE Grade 8
    00000000000000
    1 1/4"-7
    1 7/8"31/32"SAE Grade 8
    00000000000000
    1 1/2"-6
    2 1/4"1 1/16"SAE Grade 8
    00000000000000
     
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