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    46 Products

    Center-Lock Distorted-Thread Locknuts

    Image of Product. Front orientation. Locknuts. Center-Lock Distorted-Thread Locknuts.
    Also known as reversible locknuts, these thread on from either side, so you don't have to worry about fastening them incorrectly and damaging your screw. The irregularly shaped threads in the middle grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, 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. Nuts are not reusable.
    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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    		7/16"7/32"SAE Grade 2
    		10000000000000000
    1/4"-28
    		7/16"7/32"SAE Grade 2
    		10000000000000000
    5/16"-18
    		1/2"17/64"SAE Grade 2
    		1000000000000000
    5/16"-24
    		1/2"17/64"SAE Grade 2
    		1000000000000000
    3/8"-16
    		9/16"21/64"SAE Grade 2
    		10000000000000000
    3/8"-24
    		9/16"21/64"SAE Grade 2
    		10000000000000000
    7/16"-14
    		11/16"3/8"SAE Grade 2
    		5000000000000000
    7/16"-20
    		11/16"3/8"SAE Grade 2
    		5000000000000000
    1/2"-13
    		3/4"7/16"SAE Grade 2
    		5000000000000000
    1/2"-20
    		3/4"7/16"SAE Grade 2
    		5000000000000000
    5/8"-11
    		15/16"35/64"SAE Grade 2
    		2500000000000000
    5/8"-18
    		15/16"35/64"SAE Grade 2
    		2500000000000000
    3/4"-10
    		1 1/8"41/64"SAE Grade 2
    		1000000000000000
    3/4"-16
    		1 1/8"41/64"SAE Grade 2
    		1000000000000000
    1"-14
    		1 1/2"55/64"SAE Grade 2
    		500000000000000
     

    Top-Lock Distorted-Thread Locknuts

    Image of Product. Front orientation. Locknuts. Top-Lock Distorted-Thread Locknuts.
    Irregularly shaped threads at the top of these locknuts grip the screw for a stronger hold than nylon-insert locknuts. Although the threads prevent the nut from backing out due to vibration, 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. Nuts are not reusable.
    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.
    Thread
    Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    6-32
    		5/16"7/64"SAE Grade 2
    		100000000000000000
    8-32
    		11/32"1/8"SAE Grade 2
    		1000000000000000
    10-24
    		3/8"1/8"SAE Grade 2
    		10000000000000000
    10-32
    		3/8"1/8"SAE Grade 2
    		10000000000000000
    1/4"-20
    		7/16"7/32"SAE Grade 2
    		10000000000000000
    1/4"-28
    		7/16"7/32"SAE Grade 2
    		10000000000000000
    5/16"-18
    		1/2"17/64"SAE Grade 2
    		10000000000000000
    5/16"-24
    		1/2"17/64"SAE Grade 2
    		10000000000000000
    3/8"-16
    		9/16"21/64"SAE Grade 2
    		5000000000000000
    1/2"-13
    		3/4"7/16"SAE Grade 2
    		100000000000000
    1/2"-20
    		3/4"7/16"SAE Grade 2
    		2500000000000000
     

    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
    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
     

    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.
    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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