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    98 Products

    Locknuts for use with Cotter Pins
    3D CAD models available

    Use these locknuts to secure rotating parts subjected to mild vibration, such as the wheels on carts and hand trucks. They’re not recommended for use on parts exposed to high vibration because the pin can shear under prolonged stress. These nuts are reusable, but you'll need a new cotter pin (not included) with each use.
    Medium-Strength Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    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.
    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.
    Thread Size
    Wd.
    Ht.
    Fastener Strength
    Grade/Class
    For Cotter
    Pin Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"SAE Grade 5
    1/16"__25000000000000000
    1/4"-28
    7/16"7/32"SAE Grade 5
    1/16"__100000000000000
    5/16"-18
    1/2"17/64"SAE Grade 5
    5/64"__2500000000000000
    3/8"-16
    9/16"21/64"SAE Grade 5
    7/64"__2500000000000000
    3/8"-24
    9/16"21/64"SAE Grade 5
    7/64"__1000000000000000
    7/16"-14
    11/16"3/8"SAE Grade 5
    7/64"__2500000000000000
    7/16"-20
    11/16"3/8"SAE Grade 5
    7/64"__100000000000000
    1/2"-13
    3/4"7/16"SAE Grade 5
    7/64"__100000000000000
    1/2"-20
    3/4"7/16"SAE Grade 5
    7/64"__1000000000000000
    9/16"-12
    7/8"31/64"SAE Grade 5
    9/64"__1000000000000000
    9/16"-18
    7/8"31/64"SAE Grade 5
    9/64"__1000000000000000
    5/8"-11
    15/16"35/64"SAE Grade 5
    5/32"__1000000000000000
    5/8"-18
    15/16"35/64"SAE Grade 5
    5/32"__1000000000000000
    3/4"-10
    1 1/8"41/64"SAE Grade 5
    5/32"__500000000000000
    3/4"-16
    1 1/8"41/64"SAE Grade 5
    5/32"__500000000000000
    7/8"-14
    1 5/16"49/64"SAE Grade 5
    3/16"__10000000000000
    1"-8
    1 1/2"55/64"SAE Grade 5
    3/16"__10000000000000
    1"-14
    1 1/2"55/64"SAE Grade 5
    3/16"__10000000000000
    1 1/4"-7
    1 7/8"1 3/32"SAE Grade 5
    5/16"__10000000000000
    1 1/4"-12
    1 7/8"1 3/32"SAE Grade 5
    5/16"__100000000000000
    M6 × 1 mm10 mm7.5 mmISO Class 8
    1.6 mmDIN 93550000000000000
    M8 × 1.25 mm13 mm9.5 mmISO Class 8
    2 mmDIN 93550000000000000
    M10 × 1.5 mm17 mm12 mmISO Class 8
    2.5 mmDIN 93550000000000000
    M12 × 1.5 mm19 mm15 mmISO Class 8
    3.2 mmDIN 93550000000000000
    M12 × 1.75 mm19 mm15 mmISO Class 8
    3.2 mmDIN 93550000000000000
    M14 × 1.5 mm22 mm16 mmISO Class 8
    3.2 mmDIN 93510000000000000
    M14 × 2 mm22 mm16 mmISO Class 8
    3.2 mmDIN 93510000000000000
    M16 × 1.5 mm24 mm19 mmISO Class 8
    4 mmDIN 9351000000000000000
    M16 × 2 mm24 mm19 mmISO Class 8
    4 mmDIN 93550000000000000
    M18 × 2.5 mm27 mm21 mmISO Class 8
    4 mmDIN 93510000000000000
    M20 × 2.5 mm30 mm22 mmISO Class 8
    4 mmDIN 935500000000000000
    M24 × 2 mm36 mm27 mmISO Class 8
    5 mmDIN 93510000000000000
    M24 × 3 mm36 mm27 mmISO Class 8
    5 mmDIN 93510000000000000
    M27 × 3 mm41 mm30 mmISO Class 8
    5 mmDIN 935100000000000000
    M30 × 3.5 mm46 mm33 mmISO Class 8
    6.3 mmDIN 935100000000000000
     
    Steel
    M12 × 1.5 mm19 mm15 mmISO Class 8
    3.2 mmDIN 935100000000000000
    M14 × 1.5 mm22 mm16 mmISO Class 8
    3.2 mmDIN 93510000000000000
    M14 × 2 mm22 mm16 mmISO Class 8
    3.2 mmDIN 93510000000000000
    M16 × 1.5 mm24 mm19 mmISO Class 8
    4 mmDIN 93510000000000000
    M16 × 2 mm24 mm19 mmISO Class 8
    4 mmDIN 93510000000000000
    M18 × 2.5 mm27 mm21 mmISO Class 8
    4 mmDIN 93510000000000000
    M20 × 2.5 mm30 mm22 mmISO Class 8
    4 mmDIN 93510000000000000
    M24 × 3 mm36 mm27 mmISO Class 8
    5 mmDIN 93510000000000000
    M30 × 3.5 mm46 mm33 mmISO Class 8
    6.3 mmDIN 935100000000000000
    M36 × 3 mm55 mm38 mmISO Class 8
    6.3 mmDIN 935100000000000000
    M36 × 4 mm55 mm38 mmISO Class 8
    6.3 mmDIN 935100000000000000
    M42 × 4.5 mm65 mm46 mmISO Class 8
    8 mmDIN 935100000000000000
    M48 × 5 mm75 mm50 mmISO Class 8
    8 mmDIN 935100000000000000
    M56 × 5.5 mm85 mm57 mmISO Class 8
    8 mmDIN 935100000000000000
     
    Low-Strength Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    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-Oxide Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.
    Ht.
    For Cotter
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"1/16"50000000000000000
    1/4"-28
    7/16"7/32"1/16"5000000000000000
    5/16"-18
    1/2"17/64"5/64"250000000000000
    5/16"-24
    1/2"17/64"5/64"250000000000000
    3/8"-16
    9/16"21/64"7/64"2500000000000000
    3/8"-24
    9/16"21/64"7/64"2500000000000000
    7/16"-14
    11/16"3/8"3/32"2500000000000000
    7/16"-20
    11/16"3/8"3/32"2500000000000000
    1/2"-13
    3/4"7/16"1/8"2500000000000000
    1/2"-20
    3/4"7/16"1/8"2500000000000000
    9/16"-12
    7/8"31/64"7/64"1000000000000000
    9/16"-18
    7/8"31/64"7/64"50000000000000
    5/8"-11
    15/16"35/64"5/32"100000000000000
    5/8"-18
    15/16"35/64"5/32"100000000000000
    3/4"-10
    1 1/8"21/32"5/32"1000000000000000
    3/4"-16
    1 1/8"21/32"5/32"1000000000000000
    7/8"-9
    1 5/16"3/4"5/32"500000000000000
    7/8"-14
    1 5/16"3/4"5/32"50000000000000
    1"-8
    1 1/2"55/64"3/16"500000000000000
    1"-14
    1 1/2"55/64"3/16"500000000000000
    1 1/4"-7
    1 7/8"1 3/32"9/32"10000000000000
    1 1/4"-12
    1 7/8"1 1/16"9/32"10000000000000
    1 1/2"-6
    2 1/4"1 5/16"5/16"100000000000000
    1 1/2"-12
    2 1/4"1 5/16"5/16"100000000000000
    1 3/4"-5
    2 5/8"1 1/2"3/8"100000000000000
    1 3/4"-12
    2 5/8"1 1/2"3/8"100000000000000
    2"-4 1/2
    3"1 23/32"3/8"100000000000000
    2"-12
    3"1 23/32"3/8"100000000000000
     
    Black-Oxide Steel
    1 1/2"-12
    2 1/4"1 9/32"5/16"100000000000000
     
    Steel
    1/4"-20
    7/16"7/32"1/16"250000000000000
    5/16"-24
    1/2"17/64"5/64"250000000000000
    1"-14
    1 1/2"55/64"3/16"10000000000000
     
    Corrosion-Resistant Stainless Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    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.
    For Cotter
    Pin Dia.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    3/8"1/4"3/64"5000000000000000
    1/4"-20
    7/16"9/32"1/16"50000000000000
    1/4"-28
    7/16"9/32"1/16"50000000000000
    5/16"-18
    1/2"21/64"5/64"500000000000000
    5/16"-24
    1/2"21/64"5/64"500000000000000
    3/8"-16
    9/16"13/32"3/32"10000000000000
    3/8"-24
    9/16"13/32"3/32"10000000000000
    1/2"-13
    3/4"9/16"1/8"10000000000000
    1/2"-20
    3/4"9/16"1/8"10000000000000
    5/8"-11
    15/16"23/32"5/32"10000000000000
    5/8"-18
    15/16"23/32"5/32"10000000000000
    3/4"-10
    1 1/8"13/16"5/32"10000000000000
    3/4"-16
    1 1/8"13/16"5/32"100000000000000
    7/8"-9
    1 5/16"29/32"5/32"100000000000000
    1"-8
    1 1/2"1"3/16"100000000000000
    1 1/4"-7
    1 7/8"1 1/4"7/32"100000000000000
    1 1/2"-6
    2 1/4"1 1/2"1/4"100000000000000
     
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