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    42 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.
    Plastic
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Nylon 6/6—Slippery and abrasion resistant, these nuts thread on smoothly and stand up to daily wear and tear. Nylon will swell and weaken when exposed to moisture, so it's best for dry environments.
    Pkg.
    Thread Size
    Wd.
    Ht.
    Temp. Range,
    ° F
    Choose a Color
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    Nylon 6/6
    4-40
    1/4"9/32"-40 to 185
    Black
    ,
    Off-White
    10094922A300000000000000000000
    6-32
    19/64"11/32"-40 to 185
    Black
    ,
    Off-White
    10094922A305000000000000000
    8-32
    21/64"3/8"-40 to 185
    Black
    ,
    Off-White
    10094922A310000000000000000
    10-24
    23/64"13/32"-40 to 185
    Black
    ,
    Off-White
    10094922A315000000000000000
    10-32
    23/64"13/32"-40 to 185
    Black
    ,
    Off-White
    10094922A320000000000000000
    1/4"-20
    27/64"15/32"-40 to 185
    Black
    ,
    Off-White
    10094922A325000000000000000
    1/4"-28
    27/64"15/32"-40 to 185
    Black
    ,
    Off-White
    10094922A330000000000000000
    5/16"-18
    1/2"17/32"-40 to 185
    Black
    ,
    Off-White
    5094922A335000000000000000
    5/16"-24
    1/2"17/32"-40 to 185
    Black
    ,
    Off-White
    5094922A340000000000000000
    3/8"-16
    9/16"5/8"-40 to 185
    Black
    ,
    Off-White
    2594922A34500000000000000
    3/8"-24
    9/16"5/8"-40 to 185
    Black
    ,
    Off-White
    2594922A3500000000000000
    7/16"-14
    3/4"13/16"-40 to 185
    Black
    ,
    Off-White
    1094922A430000000000000
    1/2"-13
    3/4"13/16"-40 to 185
    Black
    ,
    Off-White
    2594922A355000000000000000
    1/2"-20
    3/4"13/16"-40 to 185
    Black
    ,
    Off-White
    1094922A360000000000000
    5/8"-11
    15/16"31/32"-40 to 185
    Black
    ,
    Off-White
    2094922A365000000000000000
    M4 × 0.7 mm7 mm8 mm-40 to 185
    Black
    ,
    Off-White
    10090527A505000000000000000
    M5 × 0.8 mm8 mm10 mm-40 to 185
    Black
    ,
    Off-White
    10090527A510000000000000000
    M6 × 1 mm10 mm12 mm-40 to 185
    Black
    ,
    Off-White
    10090527A515000000000000000
    M8 × 1.25 mm13 mm15 mm-40 to 185
    Black
    ,
    Off-White
    5090527A520000000000000000
    M10 × 1.5 mm17 mm18 mm-40 to 185
    Black
    ,
    Off-White
    2590527A525000000000000000
    M12 × 1.75 mm19 mm20.5 mm-40 to 185
    Black
    ,
    Off-White
    2590527A530000000000000000
     

    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
     
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