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    29 Products

    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
    		7.110093825A210000000
    M4 × 0.7 mm74.1ISO Class 8
    		8.510093825A22000000
    M5 × 0.8 mm85.2ISO Class 8
    		9.510093825A23000000
    M6 × 1 mm106.2ISO Class 8
    		125093825A24000000
    M8 × 1.25 mm138.5ISO Class 8
    		15.52593825A25000000
    M10 × 1.5 mm179.7ISO Class 8
    		20.11093825A26000000
     
    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"10090328A10100000
    6-32
    		5/16"9/64"0.344"10090328A1020000
    8-32
    		11/32"5/32"0.375"10090328A1030000
    10-24
    		3/8"5/32"0.406"10090328A10400000
    10-32
    		3/8"5/32"0.406"10090328A10500000
    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
     

    Low-Strength Steel Square Nuts

    Image of Product. Front orientation. Square Nuts. Low-Strength Steel Square Nuts.
    Large flat sides make these nuts easy to grip with a wrench and keep them from rotating in channels and square holes. About half the strength of medium-strength steel square nuts, use them in light duty fastening applications, such as securing access panels.
    Black-Zinc-Plated Steel—Black-zinc-plated steel square nuts resist corrosion in wet environments and have a black finish that blends in with dark surfaces.
    Thread Size
    Wd.
    Ht.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Black-Zinc-Plated Steel
    1/4"-20
    		7/16"3/16"—10094859A111000000
    5/16"-18
    		9/16"7/32"—5094859A12200000
    3/8"-16
    		5/8"1/4"—5094859A13300000
     
    Black-Zinc-Plated Steel—ISO Class 5
    M4 × 0.7 mm7 mm3 mmDIN 5572596887A1180000
    M5 × 0.8 mm8 mm4 mmDIN 5572596887A1190000
    M6 × 1 mm10 mm5 mmDIN 5572596887A1210000
    M8 × 1.25 mm13 mm6.5 mmDIN 5571096887A1220000
    M10 × 1.5 mm17 mm8 mmDIN 5571096887A12300000
    M16 × 2 mm24 mm13 mmDIN 557196887A1250000
     
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