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    20 Products

    Locking Type

    Hex Nut Profile

    Locknuts with External-Tooth Lock Washer

    To save on assembly time, these locknuts combine a hex nut with a free-spinning lock washer, so you can twist them into place by hand. Once the nut is against your material surface, tighten it down with a wrench or socket to get the teeth to bite. Although these nuts install more quickly than nylon-insert locknuts, they don't hold up as well against vibration and can mar your material. As long as the washer stays intact, you can reuse them. Also known as Keps and K-lock nuts.
    Medium-Strength Steel
    Image of Product. Front orientation. ZoomedIn view. Locknuts. Locknuts with External-Tooth Lock Washer.
    These Grade 5, Grade C, or Class 8 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.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Washer
    OD, mm
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    M3 × 0.5 mm5.53Class 8
    		7.1—10093825A210000000
    M4 × 0.7 mm74.1Class 8
    		8.5Material Certificate
    		10093825A22000000
    M5 × 0.8 mm85.2Class 8
    		9.5—10093825A23000000
    M6 × 1 mm106.2Class 8
    		12Material Certificate
    		5093825A24000000
    M8 × 1.25 mm138.5Class 8
    		15.5Material Certificate
    		2593825A25000000
    M10 × 1.5 mm179.7Class 8
    		20.1—1093825A26000000
     
    Low-Strength Steel
    Image of Product. Front orientation. ZoomedIn view. Locknuts. Locknuts with External-Tooth Lock Washer.
    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.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Thread
    Size
    Wd.
    Ht.
    Washer
    OD
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    4-40
    		1/4"1/8"0.281"Material Certificate
    		10090328A10100000
    6-32
    		5/16"9/64"0.344"Material Certificate
    		10090328A1020000
    8-32
    		11/32"5/32"0.375"Material Certificate
    		10090328A1030000
    10-24
    		3/8"5/32"0.406"—10090328A1040000
    10-32
    		3/8"5/32"0.406"—10090328A1050000
    1/4"-20
    		7/16"7/32"0.5"—10090328A10600000
     

    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.
    Black-Zinc-Plated Steel—The dark zinc plating withstands occasional exposure to moisture while creating a finished look.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    6-32
    		5/16"1/8"2202594627A11000000
    8-32
    		11/32"11/64"2202594627A1200000
    10-24
    		3/8"11/64"2202594627A1300000
    10-32
    		3/8"11/64"2202594627A1400000
    12-24
    		7/16"13/64"2202594627A1500000
    1/4"-20
    		7/16"13/64"2202594627A1600000
    5/16"-18
    		1/2"1/4"2201094627A1700000
    3/8"-16
    		9/16"17/64"2201094627A1800000
     
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