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    21 Products

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. 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
    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
    8-32
    		11/32"15/64"22010000000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    8-32
    		11/32"15/64"22050000000000000
     
    Corrosion-Resistant Stainless Steel
    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
    8-32
    		11/32"15/64"22010000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    8-32
    		11/32"15/64"22010000000000000000
     
    316 Stainless Steel
    8-32
    		11/32"15/64"22010000000000000000
     

    Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Thin-Profile Nylon-Insert Locknuts.
    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.
    Low-Strength Steel
    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
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    8-32
    		11/32"11/64"22010000000000000000
     
    Black-Zinc-Plated Steel
    8-32
    		11/32"11/64"220250000000000000
     
    Black-Corrosion-Resistant-Coated Steel
    8-32
    		11/32"11/64"22050000000000000
     
    Corrosion-Resistant Stainless Steel
    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.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    8-32
    		11/32"11/64"22010000000000000000
     
    Black-Oxide 18-8 Stainless Steel
    8-32
    		11/32"3/16"22010000000000000000
     

    Mil. Spec. Thin-Profile Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Thin-Profile Nylon-Insert Locknuts.
    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
    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.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    8-32
    		11/32"3/16"MS21083N08250NASM210831000000000000000
     
    Corrosion-Resistant Stainless Steel
    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.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    8-32
    		11/32"3/16"MS21083C08250NASM21083500000000000000
     

    Mil. Spec. Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Mil. Spec. Nylon-Insert Locknuts.
    These locknuts are manufactured and tested to strict U.S. military standards for material and construction. 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
    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. Spec.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Cadmium Yellow-Chromate-Plated Steel
    8-32
    		11/32"9/32"MS21044-N082501000000000000000
     
    Corrosion-Resistant Stainless Steel
    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.
    Spec.
    Insert Max.
    Temp., ° F
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    8-32
    		11/32"9/32"MS21044C08250NASM2104410000000000000000
     

    Nylon-Insert Flange Nuts

    A nylon insert grips the screw for a stronger hold than a serrated flange, without damaging threads or marring the surface of your material. However, the insert may become brittle if exposed to high temperatures. These nuts have a flange that distributes pressure evenly across the mounting surface, so you don't need a separate washer. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. You can reuse them a handful of times, but their holding power will decrease with each use. Also known as collar nuts.
    Medium-Strength Steel
    Image of Product. Front orientation. Flange Nuts. Nylon-Insert Flange Nuts.
    Rated Grade 5, Grade F, or Class 8, these 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.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Fastener Strength
    Grade/Class
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    8-32
    		11/32"1/4"0.469"0.02"ASME Grade F
    		250100000000000000000
     

    Nylon-Insert Locknut Assortments

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknut Assortments.
    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknut Assortments.
    With a range of sizes on hand, you can use these assortments to fasten a variety of parts. 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.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    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.
    No. of
    Pieces
    Locknuts Included
    Container
    Type
    Each
    Zinc-Plated Steel
    5504-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (50 Pieces)    		Plastic Box000000000000000
     
    18-8 Stainless Steel
    5504-40 (100 Pieces)
    6-32 (100 Pieces)
    8-32 (100 Pieces)
    10-24 (100 Pieces)
    10-32 (100 Pieces)
    1/4"-20 (50 Pieces)    		Plastic Box00000000000000
     

    Nylon-Insert Cap Nuts

    Image of Product. Bottom 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.
    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
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel with Nylon 6/6 Cap
    8-32
    		9/64"11/32"23/64"SAE Grade 2
    		2502500000000000000
     
    Steel with Nylon 6/6 Cap
    8-32
    		9/64"11/32"23/64"SAE Grade 2
    		250250000000000000
     

    Press-Fit Locknuts for Sheet Metal

    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Locknuts for Sheet Metal.
    The nylon insert inside these nuts grips screws so they won't back out or loosen. Use them to keep thin parts fastened on engines and other vibrating machinery.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust and mild chemicals.
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    Head
    Ht.
    Flange
    Dia.
    Pkg.
    Qty.
    Pkg.
    Nylon-Insert Locking
     
    Steel
    8-32
    		7/32"
    		0.05"Brinell 205, Rockwell B950.16"0.31"1000000000000000
     
    18-8 Stainless Steel
    8-32
    		7/32"
    		0.05"Brinell 190, Rockwell B900.16"0.31"1000000000000000
     
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