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    156 Products

    Split Lock Washers for Socket Head Screws

    Image of Product. Front orientation. Lock Washers. Split-Lock Washer, For Socket Head Screws.
    Stop socket head screws from loosening due to mild vibration. These washers have a small diameter to fit under screws with narrow heads, but are still thick enough to keep fasteners secure. While they're not as vibration resistant as other lock washers, they are a great fit for electrical panels, light fixtures, and other light duty assemblies. Split lock washers are not reusable, and they only work with fasteners that have right-hand threads. Also known as high-collar lock washers.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these washers won't rust when exposed to moisture. However, they can't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these washers have a dark, matte coating to create a finished look. They won't rust in wet and outdoor environments, but can't hold up to harsh chemicals as well as 316 stainless steel.
    Super-Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these washers won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    Zinc-Yellow-Chromate-Plated Steel—With the same corrosion resistance as zinc-plated steel, these withstand occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these washers have a dark, matte coating that creates 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 washers to rust.
    For Screw
    Size
    ID
    OD
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    No. 2
    0.094"0.142"0.022"10098437A18000000
    No. 4
    0.120"0.173"0.022"ASME B18.21.110098437A1020000
    No. 5
    0.133"0.202"0.030"ASME B18.21.110098437A1600000
    No. 6
    0.148"0.216"0.030"ASME B18.21.110098437A1040000
    No. 8
    0.174"0.267"0.047"ASME B18.21.110098437A1060000
    No. 10
    0.200"0.294"0.047"ASME B18.21.110098437A1080000
    No. 12
    0.227"0.331"0.078"10098437A1900000
    1/4"
    0.260"0.363"0.078"ASME B18.21.110098437A1100000
    5/16"
    0.322"0.457"0.093"ASME B18.21.15098437A1120000
    3/8"
    0.385"0.550"0.125"ASME B18.21.15098437A11500000
    7/16"
    0.450"0.644"0.140"ASME B18.21.15098437A17000000
    1/2"
    0.512"0.733"0.172"ASME B18.21.12598437A1300000
    5/8"
    0.641"0.917"0.203"ASME B18.21.11098437A1350000
    3/4"
    0.766"1.105"0.218"ASME B18.21.11098437A14000000
    7/8"
    0.894"1.291"0.234"ASME B18.21.1598437A15000000
    1"
    1.024"1.478"0.250"ASME B18.21.1198437A2100000
    M3
    3.4 mm5.6 mm0.9 mm to 1.1 mmDIN 798010091111A1180000
    M3.5
    3.9 mm6.1 mm0.9 mm to 1.1 mmDIN 798010091111A1190000
    M4
    4.4 mm7.0 mm1.1 mm to 1.3 mmDIN 798010091111A1210000
    M5
    5.4 mm8.8 mm1.5 mm to 1.7 mmDIN 798010091111A1240000
    M6
    6.5 mm9.9 mm1.5 mm to 1.7 mmDIN 798010091111A1290000
    M8
    8.5 mm12.7 mm1.9 mm to 2.1 mmDIN 798010091111A1320000
    M10
    10.7 mm16.0 mm2.3 mm to 2.7 mmDIN 798010091111A13500000
    M12
    12.7 mm18.0 mm2.3 mm to 2.7 mmDIN 79805091111A1380000
    M14
    14.7 mm21.1 mm2.8 mm to 3.2 mmDIN 79801091111A1410000
    M16
    17.0 mm24.4 mm3.3 mm to 3.7 mmDIN 79801091111A1430000
    M18
    19.0 mm26.4 mm3.3 mm to 3.7 mmDIN 79801091111A1450000
    M20
    21.2 mm30.6 mm4.3 mm to 4.7 mmDIN 79801091111A14700000
    M22
    23.5 mm32.9 mm4.3 mm to 4.7 mmDIN 7980591111A14900000
    M24
    25.5 mm35.9 mm4.8 mm to 5.2 mmDIN 7980591111A1510000
    M30
    31.7 mm44.1 mm5.8 mm to 6.2 mmDIN 7980191111A15500000
     
    Black-Oxide 18-8 Stainless Steel
    No. 4
    0.120"0.173"0.022"ASME B18.21.110093711A10000000
    No. 6
    0.148"0.216"0.030"ASME B18.21.110093711A20000000
    No. 8
    0.174"0.267"0.047"ASME B18.21.110093711A30000000
    No. 10
    0.200"0.294"0.047"ASME B18.21.15093711A4000000
    1/4"
    0.260"0.363"0.078"ASME B18.21.15093711A50000000
    5/16"
    0.322"0.457"0.093"ASME B18.21.12593711A6000000
    3/8"
    0.385"0.550"0.125"ASME B18.21.11093711A7000000
    1/2"
    0.512"0.733"0.172"ASME B18.21.11093711A8000000
    5/8"
    0.641"0.917"0.203"ASME B18.21.1593711A90000000
    3/4"
    0.766"1.105"0.218"ASME B18.21.1193711A9100000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    No. 2
    0.094"0.142"0.022"10094241A2100000
    No. 4
    0.120"0.173"0.022"ASME B18.21.110094241A2200000
    No. 5
    0.133"0.202"0.030"ASME B18.21.110094241A2300000
    No. 6
    0.148"0.216"0.030"ASME B18.21.110094241A2400000
    No. 8
    0.174"0.267"0.047"ASME B18.21.110094241A2500000
    No. 10
    0.200"0.294"0.047"ASME B18.21.110094241A2600000
    1/4"
    0.260"0.363"0.078"ASME B18.21.110094241A2700000
    5/16"
    0.322"0.457"0.093"ASME B18.21.15094241A2800000
    3/8"
    0.385"0.550"0.125"ASME B18.21.15094241A29000000
    7/16"
    0.450"0.644"0.140"ASME B18.21.12594241A31000000
    1/2"
    0.512"0.733"0.172"ASME B18.21.11094241A3200000
    5/8"
    0.641"0.917"0.203"ASME B18.21.11094241A33000000
    3/4"
    0.766"1.105"0.218"ASME B18.21.1594241A3400000
    7/8"
    0.894"1.291"0.234"ASME B18.21.1194241A3500000
    1"
    1.024"1.478"0.250"ASME B18.21.1194241A3600000
    1 1/4"
    1.280"1.790"0.313"ASME B18.21.1194241A3700000
    1 1/2"
    1.534"2.159"0.375"ASME B18.21.1194241A38000000
    M3
    3.4 mm5.6 mm0.9 mm to 1.1 mmDIN 798010094241A5100000
    M4
    4.4 mm7.0 mm1.1 mm to 1.3 mmDIN 798010094241A5200000
    M5
    5.4 mm8.8 mm1.5 mm to 1.7 mmDIN 798010094241A5300000
    M6
    6.5 mm9.9 mm1.5 mm to 1.7 mmDIN 798010094241A5400000
    M8
    8.5 mm12.7 mm1.9 mm to 2.1 mmDIN 79805094241A5500000
    M10
    10.7 mm16.0 mm2.3 mm to 2.7 mmDIN 79805094241A56000000
    M12
    12.7 mm18.0 mm2.3 mm to 2.7 mmDIN 79802594241A57000000
    M14
    14.7 mm21.1 mm2.8 mm to 3.2 mmDIN 79801094241A5800000
    M16
    17.0 mm24.4 mm3.3 mm to 3.7 mmDIN 79801094241A5900000
    M18
    19.0 mm26.4 mm3.3 mm to 3.7 mmDIN 79801094241A6100000
    M20
    21.2 mm30.6 mm4.3 mm to 4.7 mmDIN 7980194241A6200000
    M22
    23.5 mm32.9 mm4.3 mm to 4.7 mmDIN 7980194241A6300000
    M24
    25.5 mm35.9 mm4.8 mm to 5.2 mmDIN 7980194241A6400000
    M30
    31.7 mm44.1 mm5.8 mm to 6.2 mmDIN 7980194241A65000000
     
    Zinc-Plated Steel
    No. 6
    0.148"0.216"0.030"ASME B18.21.15092961A1110000
    No. 8
    0.174"0.267"0.042"ASME B18.21.15092961A1120000
    No. 10
    0.200"0.294"0.047"ASME B18.21.15092961A1130000
    1/4"
    0.260"0.363"0.078"ASME B18.21.15092961A1140000
    5/16"
    0.322"0.457"0.093"ASME B18.21.15092961A1150000
    3/8"
    0.385"0.550"0.125"ASME B18.21.15092961A1160000
    7/16"
    0.450"0.644"0.140"ASME B18.21.12592961A11700000
    1/2"
    0.512"0.733"0.172"ASME B18.21.12592961A1180000
    5/8"
    0.641"0.917"0.203"ASME B18.21.12592961A1190000
    3/4"
    0.766"1.105"0.218"ASME B18.21.11092961A1200000
    7/8"
    0.984"1.291"0.234"ASME B18.21.1592961A1210000
    1"
    1.024"1.478"0.250"ASME B18.21.1192961A12200000
    M3
    3.4 mm5.6 mm0.9 mm to 1.1 mmDIN 798010093837A1100000
    M4
    4.4 mm7.0 mm1.1 mm to 1.3 mmDIN 798010093837A1200000
    M5
    5.4 mm8.8 mm1.5 mm to 1.7 mmDIN 798010093837A1300000
    M6
    6.5 mm9.9 mm1.5 mm to 1.7 mmDIN 798010093837A1400000
    M8
    8.5 mm12.7 mm1.9 mm to 2.1 mmDIN 798010093837A2300000
    M10
    10.7 mm16.0 mm2.3 mm to 2.7 mmDIN 798010093837A15000000
    M12
    12.7 mm18.0 mm2.3 mm to 2.7 mmDIN 798010093837A24000000
    M14
    14.7 mm21.1 mm2.8 mm to 3.2 mmDIN 79805093837A25000000
    M16
    17.0 mm24.4 mm3.3 mm to 3.7 mmDIN 79802593837A1600000
    M18
    19.0 mm26.4 mm3.3 mm to 3.7 mmDIN 79802593837A17000000
    M20
    21.2 mm30.6 mm4.3 mm to 4.7 mmDIN 79801093837A1800000
    M24
    25.5 mm35.9 mm4.8 mm to 5.2 mmDIN 79801093837A1900000
    M27
    28.5 mm38.9 mm4.8 mm to 5.2 mmDIN 7980593837A2600000
    M30
    31.7 mm44.1 mm5.8 mm to 6.2 mmDIN 7980593837A21000000
    M36
    37.7 mm52.2 mm6.7 mm to 7.3 mmDIN 7980193837A2200000
     
    Zinc-Yellow-Chromate-Plated Steel
    M4
    4.1 mm7.0 mm1.1 mm to 1.3 mmDIN 798010093837A3100000
    M5
    5.1 mm8.8 mm1.5 mm to 1.7 mmDIN 79802593837A3200000
    M6
    6.1 mm9.9 mm1.5 mm to 1.7 mmDIN 798010093837A3300000
    M8
    8.1 mm12.7 mm1.9 mm to 2.1 mmDIN 798010093837A3400000
    M10
    10.2 mm16.0 mm2.3 mm to 2.7 mmDIN 798010093837A35000000
    M12
    12.2 mm18.0 mm2.3 mm to 2.7 mmDIN 798010093837A36000000
    M16
    16.2 mm24.4 mm3.3 mm to 3.7 mmDIN 79802593837A37000000
     
    Black-Oxide Steel
    No. 4
    0.117"0.173"0.022"ASME B18.21.15092962A2100000
    No. 6
    0.145"0.216"0.030"ASME B18.21.15092962A2200000
    No. 8
    0.174"0.267"0.042"ASME B18.21.15092962A1110000
    No. 10
    0.200"0.294"0.047"ASME B18.21.15092962A1120000
    1/4"
    0.260"0.363"0.078"ASME B18.21.15092962A1130000
    5/16"
    0.322"0.457"0.093"ASME B18.21.15092962A1140000
    3/8"
    0.385"0.550"0.125"ASME B18.21.11092962A1150000
    7/16"
    0.450"0.644"0.140"ASME B18.21.12592962A1160000
    1/2"
    0.512"0.733"0.172"ASME B18.21.12592962A1170000
    5/8"
    0.641"0.917"0.203"ASME B18.21.11092962A11800000
    3/4"
    0.766"1.105"0.218"ASME B18.21.1592962A1190000
    7/8"
    0.984"1.291"0.234"ASME B18.21.1592962A1200000
    1"
    1.024"1.478"0.250"ASME B18.21.1192962A1210000
    1 1/8"
    1.153"1.663"0.313"ASME B18.21.1192962A1220000
    1 1/4"
    1.280"1.790"0.313"ASME B18.21.1192962A1230000
    M3
    3.4 mm5.6 mm0.9 mm to 1.1 mmDIN 798010091190A5100000
    M3.5
    3.9 mm6.1 mm0.9 mm to 1.1 mmDIN 798010091190A5150000
    M4
    4.4 mm7.0 mm1.1 mm to 1.3 mmDIN 798010091190A5200000
    M5
    5.4 mm8.8 mm1.5 mm to 1.7 mmDIN 798010091190A5300000
    M6
    6.5 mm9.9 mm1.5 mm to 1.7 mmDIN 798010091190A5400000
    M8
    8.5 mm12.7 mm1.9 mm to 2.1 mmDIN 798010091190A5500000
    M10
    10.7 mm16.0 mm2.3 mm to 2.7 mmDIN 798010091190A56000000
    M12
    12.7 mm18.0 mm2.3 mm to 2.7 mmDIN 798010091190A57000000
    M14
    14.7 mm21.1 mm2.8 mm to 3.2 mmDIN 798010091190A58000000
    M16
    17.0 mm24.4 mm3.3 mm to 3.7 mmDIN 79805091190A59000000
    M18
    19.0 mm26.4 mm3.3 mm to 3.7 mmDIN 79802591190A6000000
    M20
    21.2 mm30.6 mm4.3 mm to 4.7 mmDIN 79802591190A61000000
    M22
    23.5 mm32.9 mm4.3 mm to 4.7 mmDIN 79801091190A6200000
    M24
    25.5 mm35.9 mm4.8 mm to 5.2 mmDIN 79801091190A63000000
    M27
    28.5 mm38.9 mm4.8 mm to 5.2 mmDIN 7980591190A6500000
    M30
    31.7 mm44.1 mm5.8 mm to 6.2 mmDIN 7980591190A67000000
    M36
    37.7 mm52.2 mm6.7 mm to 7.3 mmDIN 7980191190A6900000
    M42
    43.7 mm60.2 mm7.7 mm to 8.3 mmDIN 7980191190A66000000
    M48
    50.5 mm67.0 mm7.7 mm to 8.3 mmDIN 7980191190A64000000
     
    Steel
    No. 4
    0.120"0.173"0.022"ASME B18.21.110090073A0050000
    No. 5
    0.133"0.202"0.030"ASME B18.21.110090073A0060000
    No. 6
    0.148"0.216"0.030"ASME B18.21.110090073A0070000
    No. 10
    0.200"0.294"0.047"ASME B18.21.110090073A0110000
    1/4"
    0.260"0.363"0.078"ASME B18.21.110090073A0290000
    5/16"
    0.322"0.457"0.093"ASME B18.21.110090073A0300000
    3/8"
    0.385"0.550"0.125"ASME B18.21.110090073A2310000
    7/16"
    0.450"0.644"0.140"ASME B18.21.110090073A23400000
    1/2"
    0.512"0.733"0.172"ASME B18.21.110090073A23700000
    5/8"
    0.641"0.917"0.203"ASME B18.21.15090073A24000000
    3/4"
    0.766"1.105"0.218"ASME B18.21.12590073A2430000
    7/8"
    0.894"1.291"0.234"ASME B18.21.12590073A24600000
    1"
    1.024"1.478"0.250"ASME B18.21.11090073A0380000
    1 1/8"
    1.153"1.663"0.313"ASME B18.21.1590073A33300000
    1 1/4"
    1.280"1.790"0.313"ASME B18.21.11090073A04000000
    1 1/2"
    1.534"2.159"0.375"ASME B18.21.1590073A04200000
     
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