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    79 Products

    Performance

    Locking Type

    Locking Type

    Cap Nuts with Threadlocker

    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.
    Stainless Steel
    Image of Product. Front orientation. Contains Annotated, Border. Cap Nuts. Cap Nuts with Threadlocker.
    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.
    Highly-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.
    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
     
    Highly-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
     

    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 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 9862451000000000000000
    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. 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
    		25010000000000000000
     

    Distorted-Thread Cap Nuts

    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.
    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.
    Highly-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.
    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
     
    Highly-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
    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.
    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
     
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