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    20 Products

    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"2202500000000000000
    8-32
    		11/32"11/64"220250000000000000
    10-24
    		3/8"11/64"220250000000000000
    10-32
    		3/8"11/64"220250000000000000
    12-24
    		7/16"13/64"220250000000000000
    1/4"-20
    		7/16"13/64"220250000000000000
    5/16"-18
    		1/2"1/4"220100000000000000
    3/8"-16
    		9/16"17/64"220100000000000000
     

    Locknuts with External-Tooth Lock Washer

    Image of Product. Front orientation. ZoomedIn view. Locknuts. 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
    These Grade 5 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
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    M3 × 0.5 mm5.53ISO Class 8
    		7.1100000000000000000
    M4 × 0.7 mm74.1ISO Class 8
    		8.510000000000000000
    M5 × 0.8 mm85.2ISO Class 8
    		9.510000000000000000
    M6 × 1 mm106.2ISO Class 8
    		125000000000000000
    M8 × 1.25 mm138.5ISO Class 8
    		15.52500000000000000
    M10 × 1.5 mm179.7ISO Class 8
    		20.11000000000000000
     
    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.
    Washer
    OD
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    4-40
    		1/4"1/8"0.281"10000000000000000
    6-32
    		5/16"9/64"0.344"1000000000000000
    8-32
    		11/32"5/32"0.375"1000000000000000
    10-24
    		3/8"5/32"0.406"10000000000000000
    10-32
    		3/8"5/32"0.406"10000000000000000
    1/4"-20
    		7/16"7/32"0.5"10000000000000000
     
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