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    19 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.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-24
    3/16"3/8"13/32"1000000000000000
    10-24
    7/32"3/8"11/32"1000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    10-24
    3/16"3/8"13/32"1000000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    10-24
    3/16"3/8"13/32"500000000000000
     
    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.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    10-24
    3/16"3/8"13/32"50000000000000000
     
    Black Corrosion-Resistant-Coated Steel
    10-24
    3/16"3/8"13/32"50000000000000
     
    Nickel-Plated Steel
    10-24
    3/16"3/8"5/16"1000000000000000
     
    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.
    Ht.
    Temp. Range,
    ° F
    Choose a Color
    Pkg.
    Qty.
    Pkg.
    Nylon 6/6
    10-24
    23/64"13/32"-40 to 185
    Black
    ,
    Off-White
    100000000000000000
     
    Lightweight Aluminum
    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    2011 Aluminum—One-third the weight of steel, these nuts are commonly used in robotics, automation, and other applications that have weight limitations. They're an alternative to stainless steel for rust resistance but are not as strong.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    2011 Aluminum
    10-24
    5/32"3/8"11/32"25000000000000000
     
    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.
    Nickel-Plated Brass—In addition to creating a polished appearance, the nickel plating offers better corrosion resistance than plain brass to stand up to solvents and mild chemicals.
    Chrome-Plated Brass—The brightest, shiniest finish we offer, this plating has a mirror-like appearance that's often used in decorative applications. It has better corrosion resistance than plain brass to stand up to solvents and mild chemicals.
    Thread
    Size
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Brass
    10-24
    5/32"3/8"11/32"25000000000000000
     
    Nickel-Plated Brass
    10-24
    5/32"3/8"11/32"2500000000000000
     
    Chrome-Plated Brass
    10-24
    5/32"3/8"11/32"100000000000000
     

    Nylon-Insert Cap Nuts
    3D CAD models available

    Image of Product. Front orientation. Cap Nuts. 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
    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.
    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
    10-24
    9/64"3/8"23/64"SAE Grade 2
    2502500000000000000
     

    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.
    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
    10-24
    3/16"3/8"13/32"5000000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    10-24
    3/16"3/8"13/32"500000000000000
     

    Distorted-Thread Cap Nuts
    3D CAD models available

    Image of Product. Bottom orientation. Cap Nuts. 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.
    Corrosion-Resistant Stainless Steel
    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
    10-24
    3/16"3/8"13/32"10000000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    10-24
    3/16"3/8"13/32"10000000000000
     
    Low-Strength Steel
    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
    10-24
    3/16"3/8"13/32"SAE Grade 2
    25000000000000000
     

    Open-End Cap Nuts
    3D CAD models available

    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.
    Corrosion-Resistant 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
    Dp.
    Wd.
    Ht.
    Each
    18-8 Stainless Steel
    10-24
    5/16"7/16"5/16"00000000000000
     
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