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    69 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.
    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.
    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., mm
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M3 × 0.5 mm3.85.56DIN 15871000000000000000
    M4 × 0.7 mm5.778DIN 1587250000000000000
    M5 × 0.8 mm4.5810DIN 1587250000000000000
    M6 × 1 mm7.71012DIN 1587200000000000000
    M8 × 1.25 mm10.71315DIN 1587100000000000000
    M10 × 1.5 mm12.71718DIN 158750000000000000
    M12 × 1.75 mm15.71922DIN 158750000000000000
    M14 × 2 mm17.72225DIN 158710000000000000
    M16 × 2 mm20.62428DIN 158710000000000000
    M18 × 2.5 mm24.62732DIN 158710000000000000
    M20 × 2.5 mm25.63034DIN 158710000000000000
    M22 × 2.5 mm28.63439DIN 158710000000000000
    M24 × 3 mm30.53642DIN 158710000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    M3 × 0.5 mm3.85.56DIN 1587250000000000000
    M4 × 0.7 mm5.578DIN 1587250000000000000
    M5 × 0.8 mm4.5810DIN 1587250000000000000
    M6 × 1 mm81012DIN 15872500000000000000
    M8 × 1.25 mm111315DIN 1587100000000000000
    M10 × 1.5 mm131718DIN 15871000000000000000
    M12 × 1.75 mm161922DIN 1587500000000000000
    M14 × 2 mm182225DIN 158710000000000000
    M16 × 2 mm212428DIN 158710000000000000
    M20 × 2.5 mm263034DIN 1587100000000000000
    M22 × 2.5 mm293439DIN 1587100000000000000
    M24 × 3 mm313642DIN 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.
    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
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm5.378DIN 158750000000000000000
    M5 × 0.8 mm3.7810DIN 15875000000000000000
    M6 × 1 mm7.71012DIN 15875000000000000000
    M8 × 1.25 mm10.71315DIN 15872500000000000000
    M10 × 1.5 mm12.71718DIN 1587100000000000000
    M12 × 1.75 mm15.71922DIN 15871000000000000000
     
    Chrome-Plated Steel
    M4 × 0.7 mm3.978DIN 1587500000000000000
    M5 × 0.8 mm5.6810DIN 1587500000000000000
    M6 × 1 mm5.71012DIN 1587500000000000000
    M8 × 1.25 mm8.21315DIN 158710000000000000
    M10 × 1.5 mm9.71718DIN 158710000000000000
    M12 × 1.75 mm12.21922DIN 158710000000000000
     
    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.
    Thread Size
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M6 × 1 mm5.71012ISO Class 10
    DIN 15875000000000000000
    M8 × 1.25 mm8.21315ISO Class 10
    DIN 1587500000000000000
    M10 × 1.5 mm9.71718ISO Class 10
    DIN 158710000000000000
    M12 × 1.75 mm12.21922ISO Class 10
    DIN 1587100000000000000
     
    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.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Temp. Range,
    ° F
    Choose a Color
    Pkg.
    Qty.
    Pkg.
    Nylon 6/6
    M4 × 0.7 mm78-40 to 185
    Black
    ,
    Off-White
    100000000000000000
    M5 × 0.8 mm810-40 to 185
    Black
    ,
    Off-White
    10000000000000000
    M6 × 1 mm1012-40 to 185
    Black
    ,
    Off-White
    10000000000000000
    M8 × 1.25 mm1315-40 to 185
    Black
    ,
    Off-White
    5000000000000000
    M10 × 1.5 mm1718-40 to 185
    Black
    ,
    Off-White
    2500000000000000
    M12 × 1.75 mm1920.5-40 to 185
    Black
    ,
    Off-White
    2500000000000000
     
    Brass
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Thread Size
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Pkg.
    Qty.
    Pkg.
    Brass
    M4 × 0.7 mm5.578500000000000000
    M6 × 1 mm81012500000000000000
    M8 × 1.25 mm11131550000000000000
    M10 × 1.5 mm131718100000000000000
     

    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.
    Thread Size
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M4 × 0.7 mm2.379.6ISO Class 6
    DIN 98624550000000000000000
    M5 × 0.8 mm3.5810.5ISO Class 6
    DIN 986245250000000000000
    M6 × 1 mm3.91012ISO Class 6
    DIN 986245250000000000000
    M8 × 1.25 mm5.21314ISO Class 6
    DIN 9862452500000000000000
    M10 × 1.5 mm6.41618ISO Class 6
    DIN 9862451000000000000000
    M12 × 1.75 mm8.31823ISO Class 6
    DIN 98624550000000000000
    M16 × 2 mm11.32428ISO Class 6
    DIN 98624510000000000000
    M20 × 2.5 mm13.53035ISO Class 6
    DIN 98624510000000000000
     

    Threadlocker Cap Nuts

    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.
    Thread Size
    Thread
    Dp., mm
    Wd.,
    mm
    Ht.,
    mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M5 × 0.8 mm5.6810DIN 15875000000000000000
    M6 × 1 mm5.71012DIN 1587500000000000000
    M8 × 1.25 mm8.21315DIN 1587500000000000000
    M10 × 1.5 mm9.71718DIN 1587100000000000000
    M12 × 1.75 mm12.21922DIN 1587100000000000000
     

    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 silicone 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.
    Corrosion-Resistant 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., mm
    Wd.,
    mm
    Ht.,
    mm
    Seal Material
    Certification
    Food Industry Std.
    Each
    Super-Corrosion-Resistant 316 Stainless Steel
    M6 × 1 mm5.5108Silicone RubberEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    000000000000000
    M8 × 1.25 mm6.51310Silicone RubberEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    00000000000000
    M10 × 1.5 mm81612Silicone RubberEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    00000000000000
    M12 × 1.75 mm91814Silicone RubberEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    00000000000000
    M16 × 2 mm10.52417Silicone RubberEHEDG Certified
    FDA Compliant 21 CFR 177.2600
    00000000000000
     
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