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    98 Products

    Locknuts for use with Cotter Pins

    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, 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.
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"SAE Grade 5
    1/16"2597190A005000000
    1/4"-28
    7/16"7/32"SAE Grade 5
    1/16"1097190A1100000
    5/16"-18
    1/2"17/64"SAE Grade 5
    5/64"2597190A01000000
    3/8"-16
    9/16"21/64"SAE Grade 5
    7/64"2597190A01500000
    3/8"-24
    9/16"21/64"SAE Grade 5
    7/64"1097190A12000000
    7/16"-14
    11/16"3/8"SAE Grade 5
    7/64"2597190A02000000
    7/16"-20
    11/16"3/8"SAE Grade 5
    7/64"1097190A1300000
    1/2"-13
    3/4"7/16"SAE Grade 5
    7/64"1097190A0250000
    1/2"-20
    3/4"7/16"SAE Grade 5
    7/64"Material Certificate
    1097190A14000000
    9/16"-12
    7/8"31/64"SAE Grade 5
    9/64"1097190A15000000
    9/16"-18
    7/8"31/64"SAE Grade 5
    9/64"1097190A16000000
    5/8"-11
    15/16"35/64"SAE Grade 5
    5/32"Material Certificate
    1097190A03000000
    5/8"-18
    15/16"35/64"SAE Grade 5
    5/32"Material Certificate
    1097190A17000000
    3/4"-10
    1 1/8"41/64"SAE Grade 5
    5/32"597190A03500000
    3/4"-16
    1 1/8"41/64"SAE Grade 5
    5/32"597190A18000000
    7/8"-14
    1 5/16"49/64"SAE Grade 5
    3/16"Material Certificate
    197190A1900000
    1"-8
    1 1/2"55/64"SAE Grade 5
    3/16"197190A0400000
    1"-14
    1 1/2"55/64"SAE Grade 5
    3/16"Material Certificate
    197190A2100000
    1 1/4"-7
    1 7/8"1 3/32"SAE Grade 5
    5/16"197190A2200000
    1 1/4"-12
    1 7/8"1 3/32"SAE Grade 5
    5/16"Material Certificate
    197190A23000000
    M6 × 1 mm10 mm7.5 mmClass 8
    1.6 mm593760A2120000
    M8 × 1.25 mm13 mm9.5 mmClass 8
    2 mm593760A2220000
    M10 × 1.5 mm17 mm12 mmClass 8
    2.5 mm593760A2330000
    M12 × 1.75 mm19 mm15 mmClass 8
    3.2 mmMaterial Certificate
    593760A3170000
    M12 × 1.5 mm19 mm15 mmClass 8
    3.2 mm593760A1260000
    M14 × 2 mm22 mm16 mmClass 8
    3.2 mm193760A1110000
    M14 × 1.5 mm22 mm16 mmClass 8
    3.2 mm193760A1270000
    M16 × 2 mm24 mm19 mmClass 8
    4 mm593760A32800000
    M16 × 1.5 mm24 mm19 mmClass 8
    4 mm1093760A12800000
    M18 × 2.5 mm27 mm21 mmClass 8
    4 mm193760A1120000
    M20 × 2.5 mm30 mm22 mmClass 8
    4 mm593760A33700000
    M24 × 3 mm36 mm27 mmClass 8
    5 mm193760A3400000
    M24 × 2 mm36 mm27 mmClass 8
    5 mmMaterial Certificate
    193760A12900000
    M27 × 3 mm41 mm30 mmClass 8
    5 mm193760A11300000
    M30 × 3.5 mm46 mm33 mmClass 8
    6.3 mmMaterial Certificate
    193760A11400000
     
    Steel
    M12 × 1.5 mm19 mm15 mmClass 8
    3.2 mm1093760A1310000
    M14 × 2 mm22 mm16 mmClass 8
    3.2 mm193760A1150000
    M14 × 1.5 mm22 mm16 mmClass 8
    3.2 mm193760A1320000
    M16 × 2 mm24 mm19 mmClass 8
    4 mm193760A1160000
    M16 × 1.5 mm24 mm19 mmClass 8
    4 mm193760A1330000
    M18 × 2.5 mm27 mm21 mmClass 8
    4 mmMaterial Certificate
    193760A1170000
    M20 × 2.5 mm30 mm22 mmClass 8
    4 mm193760A1180000
    M24 × 3 mm36 mm27 mmClass 8
    5 mm193760A1190000
    M30 × 3.5 mm46 mm33 mmClass 8
    6.3 mm193760A12100000
    M36 × 4 mm55 mm38 mmClass 8
    6.3 mm193760A12200000
    M36 × 3 mm55 mm38 mmClass 8
    6.3 mm193760A13400000
    M42 × 4.5 mm65 mm46 mmClass 8
    8 mm193760A12300000
    M48 × 5 mm75 mm50 mmClass 8
    8 mm193760A12400000
    M56 × 5.5 mm85 mm57 mmClass 8
    8 mmMaterial Certificate
    193760A12500000
     
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    1/4"-20
    7/16"7/32"1/16"5095030A110000000
    1/4"-28
    7/16"7/32"1/16"5095030A12000000
    5/16"-18
    1/2"17/64"5/64"2595030A1300000
    5/16"-24
    1/2"17/64"5/64"Material Certificate
    2595030A1400000
    3/8"-16
    9/16"21/64"7/64"2595030A15000000
    3/8"-24
    9/16"21/64"7/64"2595030A16000000
    7/16"-14
    11/16"3/8"3/32"2595030A17000000
    7/16"-20
    11/16"3/8"3/32"2595030A18000000
    1/2"-13
    3/4"7/16"1/8"2595030A19000000
    1/2"-20
    3/4"7/16"1/8"2595030A21000000
    9/16"-12
    7/8"31/64"7/64"1095030A22000000
    9/16"-18
    7/8"31/64"7/64"595030A2300000
    5/8"-11
    15/16"35/64"5/32"1095030A2400000
    5/8"-18
    15/16"35/64"5/32"1095030A2500000
    3/4"-10
    1 1/8"21/32"5/32"1095030A26000000
    3/4"-16
    1 1/8"21/32"5/32"1095030A27000000
    7/8"-9
    1 5/16"3/4"5/32"595030A28000000
    7/8"-14
    1 5/16"3/4"5/32"595030A29000000
    1"-8
    1 1/2"55/64"3/16"Material Certificate
    595030A31000000
    1"-14
    1 1/2"55/64"3/16"595030A32000000
    1 1/4"-7
    1 7/8"1 3/32"9/32"195030A3500000
    1 1/4"-12
    1 7/8"1 1/16"9/32"195030A3600000
    1 1/2"-6
    2 1/4"1 5/16"5/16"195030A37000000
    1 1/2"-12
    2 1/4"1 5/16"5/16"195030A38000000
    1 3/4"-5
    2 5/8"1 1/2"3/8"Material Certificate
    195030A39000000
    1 3/4"-12
    2 5/8"1 1/2"3/8"Material Certificate
    195030A41000000
    2"-4 1/2
    3"1 23/32"3/8"Material Certificate
    195030A42000000
    2"-12
    3"1 23/32"3/8"195030A43000000
     
    Black-Oxide Steel
    1 1/2"-12
    2 1/4"1 9/32"5/16"195030A61000000
     
    Steel
    1/4"-20
    7/16"7/32"1/16"2595030A5100000
    5/16"-24
    1/2"17/64"5/64"2595030A5200000
    1"-14
    1 1/2"55/64"3/16"195030A5300000
     
    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.
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    10-32
    3/8"1/4"3/64"591853A510000000
    1/4"-20
    7/16"9/32"1/16"591853A0290000
    1/4"-28
    7/16"9/32"1/16"591853A51500000
    5/16"-18
    1/2"21/64"5/64"591853A03000000
    5/16"-24
    1/2"21/64"5/64"591853A52000000
    3/8"-16
    9/16"13/32"3/32"191853A0310000
    3/8"-24
    9/16"13/32"3/32"191853A5250000
    1/2"-13
    3/4"9/16"1/8"Material Certificate
    191853A0330000
    1/2"-20
    3/4"9/16"1/8"191853A5350000
    5/8"-11
    15/16"23/32"5/32"Material Certificate
    191853A0350000
    5/8"-18
    15/16"23/32"5/32"Material Certificate
    191853A5450000
    3/4"-10
    1 1/8"13/16"5/32"Material Certificate
    191853A0360000
    3/4"-16
    1 1/8"13/16"5/32"Material Certificate
    191853A5500000
    7/8"-9
    1 5/16"29/32"5/32"191853A03700000
    1"-8
    1 1/2"1"3/16"Material Certificate
    191853A03800000
    1 1/4"-7
    1 7/8"1 1/4"7/32"Material Certificate
    191853A04000000
    1 1/2"-6
    2 1/4"1 1/2"1/4"Material Certificate
    191853A04100000
     
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