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    155 Products

    Mil. Spec. Washers

    These washers are manufactured and tested to strict U.S. military standards for material and construction. They take the pressure off screws and nuts to protect mounting surfaces.
    Steel
    Image of Product. Front orientation. Washers. Mil. Spec. Washers.
    Low-Friction Cadmium-Plated Steel—The plating reduces friction between the washer, fastener, and mounting surface to prevent sticking when fastening and loosening. It also creates a barrier against rust that's comparable to zinc yellow-chromate plating.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil. Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Low-Friction Cadmium-Plated Steel
    No. 0
    0.063"0.099"0.015" to 0.017"NAS620-01005360N111000000
    No. 1
    0.078"0.188"0.016" to 0.025"MS27183-110098032A4130000
    No. 2
    0.089"0.149"0.015" to 0.017"NAS620-21005360N1120000
    No. 2
    0.094"0.250"0.016" to 0.025"MS27183-2ASME B18.21.110098032A4170000
    No. 2
    0.099"0.250"0.029" to 0.035"AN960-2NAS1149-FN232P10095229A2300000
    No. 3
    0.102"0.180"0.015" to 0.017"NAS620-3L255360N1130000
    No. 3
    0.102"0.180"0.031" to 0.033"NAS620-3255360N11400000
    No. 3
    0.125"0.250"0.017" to 0.028"MS27183-310098032A4210000
    No. 4
    0.115"0.209"0.015" to 0.017"NAS620-4L1005360N11500000
    No. 4
    0.115"0.209"0.031" to 0.033"NAS620-41005360N11600000
    No. 4
    0.125"0.312"0.014" to 0.018"AN960-4LNAS1149-FN416P10095229A2600000
    No. 4
    0.125"0.312"0.025" to 0.040"MS27183-4ASME B18.21.110098032A4250000
    No. 4
    0.125"0.312"0.029" to 0.035"AN960-4ASME B18.21.1, NAS1149-FN432P10095229A2700000
    No. 4
    0.125"0.375"0.025" to 0.040"MS27183-4410098032A4290000
    No. 5
    0.128"0.238"0.015" to 0.017"NAS620-5L1005360N1170000
    No. 5
    0.128"0.238"0.031" to 0.033"NAS620-52505360N11800000
    No. 5
    0.141"0.281"0.025" to 0.040"MS27183-4510098032A4320000
    No. 6
    0.143"0.267"0.015" to 0.017"NAS620-6L1005360N1190000
    No. 6
    0.143"0.267"0.031" to 0.033"NAS620-61005360N12100000
    No. 6
    0.149"0.375"0.014" to 0.018"AN960-6LNAS1149-FN616P10095229A3100000
    No. 6
    0.149"0.375"0.029" to 0.035"AN960-6NAS1149-FN632P10095229A3200000
    No. 6
    0.156"0.250"0.013" to 0.020"MS27183-4310098032A4360000
    No. 6
    0.156"0.312"0.027" to 0.048"MS27183-510098032A4430000
    No. 6
    0.156"0.375"0.036" to 0.065"MS27183-6ASME B18.21.110098032A4470000
    No. 8
    0.169"0.304"0.015" to 0.017"NAS620-8L2505360N12200000
    No. 8
    0.169"0.304"0.031" to 0.033"NAS620-81005360N12300000
    No. 8
    0.174"0.375"0.014" to 0.018"AN960-8LNAS1149-FN816P10095229A3300000
    No. 8
    0.174"0.375"0.029" to 0.035"AN960-8NAS1149-FN832P10095229A3400000
    No. 8
    0.188"0.375"0.036" to 0.065"MS27183-710098032A4510000
    No. 8
    0.188"0.438"0.036" to 0.065"MS27183-41ASME B18.21.110098032A45700000
    No. 8
    0.188"0.500"0.051" to 0.080"MS27183-4610098032A4620000
    No. 10
    0.195"0.354"0.031" to 0.033"NAS620-10L1005360N1240000
    No. 10
    0.195"0.354"0.062" to 0.064"NAS620-101005360N1250000
    No. 10
    0.203"0.438"0.029" to 0.035"AN960-10LNAS1149-F0332P10095229A3700000
    No. 10
    0.203"0.438"0.059" to 0.067"AN960-10NAS1149-F0363P10095229A3800000
    No. 10
    0.203"0.875"0.053" to 0.073"AN970-3NASM97010095229A91000000
    No. 10
    0.219"0.365"0.025" to 0.040"MS27183-4710098032A4660000
    No. 10
    0.219"0.438"0.036" to 0.065"MS27183-810098032A4690000
    No. 10
    0.219"0.500"0.036" to 0.065"MS27183-42ASME B18.21.110098032A47200000
    No. 12
    0.250"0.562"0.025" to 0.040"MS27183-4910098032A4770000
    No. 12
    0.250"0.562"0.051" to 0.080"MS27183-9ASME B18.21.110098032A48100000
    No. 12
    0.250"0.625"0.025" to 0.040"MS27183-5010098032A48500000
    No. 12
    0.250"0.938"0.051" to 0.080"MS27183-482598032A4890000
    No. 12
    0.250"1.000"0.051" to 0.080"MS27183-512598032A4920000
    1/4"
    0.255"0.468"0.031" to 0.033"NAS620-416L1005360N12600000
    1/4"
    0.255"0.468"0.062" to 0.064"NAS620-4161005360N12700000
    1/4"
    0.260"0.531"0.052" to 0.072"MS20002-42591922A30400000
    1/4"
    0.265"0.500"0.029" to 0.035"AN960-416LNAS1149-F0432P10095229A4200000
    1/4"
    0.265"0.500"0.059" to 0.067"AN960-416NAS1149-F0463P10095229A4300000
    1/4"
    0.265"1.125"0.053" to 0.073"AN970-4NASM9705095229A92000000
    1/4"
    0.281"0.625"0.051" to 0.080"MS27183-10ASME B18.21.110098032A49500000
    1/4"
    0.281"0.734"0.051" to 0.080"MS27183-5210098032A49800000
    1/4"
    0.312"0.500"0.027" to 0.048"MS27183-545098032A33100000
    1/4"
    0.312"0.875"0.051" to 0.075"MS27183-532598032A33200000
    1/4"
    0.313"0.734"0.051" to 0.080"MS27183-11ASME B18.21.15098032A50100000
    5/16"
    0.324"0.593"0.052" to 0.072"MS20002-52591922A30500000
    5/16"
    0.328"0.562"0.029" to 0.035"AN960-516LNAS1149-F0532P10095229A4500000
    5/16"
    0.328"0.562"0.059" to 0.067"AN960-516NAS1149-F0563P10095229A4600000
    5/16"
    0.328"1.375"0.053" to 0.073"AN970-5NASM9705095229A93000000
    5/16"
    0.344"0.688"0.051" to 0.080"MS27183-12ASME B18.21.110098032A50500000
    5/16"
    0.375"0.625"0.027" to 0.048"MS27183-565098032A3340000
    5/16"
    0.375"0.734"0.064" to 0.094"MS27183-555098032A33500000
    5/16"
    0.375"0.875"0.064" to 0.104"MS27183-13ASME B18.21.15098032A5090000
    3/8"
    0.385"0.687"0.052" to 0.072"MS20002-62591922A30600000
    3/8"
    0.390"0.625"0.029" to 0.035"AN960-616LNAS1149-F0632P10095229A4800000
    3/8"
    0.390"0.625"0.059" to 0.067"AN960-616NAS1149-F0663P10095229A49000000
    3/8"
    0.390"1.625"0.053" to 0.073"AN970-6NASM9702595229A94000000
    3/8"
    0.406"0.812"0.051" to 0.080"MS27183-14ASME B18.21.15098032A5140000
    3/8"
    0.406"0.875"0.051" to 0.070"MS27183-575098032A34200000
    3/8"
    0.412"0.625"0.025" to 0.040"MS27183-585098032A3410000
    3/8"
    0.438"0.875"0.051" to 0.080"MS27183-605098032A34300000
    3/8"
    0.438"1.365"0.064" to 0.104"MS27183-591098032A34400000
    3/8"
    0.438"1.625"0.051" to 0.104"MS27183-611098032A34500000
    7/16"
    0.438"1.000"0.064" to 0.104"MS27183-155098032A33700000
    7/16"
    0.451"0.781"0.052" to 0.072"MS20002-72591922A30700000
    7/16"
    0.453"0.750"0.029" to 0.035"AN960-716LNAS1149-F0732P10095229A51000000
    7/16"
    0.453"0.750"0.059" to 0.067"AN960-716NAS1149-F0763P10095229A52000000
    7/16"
    0.453"1.812"0.099" to 0.119"AN970-7NASM9701095229A53000000
    7/16"
    0.469"0.734"0.051" to 0.080"MS27183-625098032A33600000
    7/16"
    0.469"0.922"0.051" to 0.080"MS27183-16ASME B18.21.15098032A33800000
    7/16"
    0.500"1.250"0.064" to 0.104"MS27183-17ASME B18.21.15098032A33900000
    1/2"
    0.515"0.875"0.029" to 0.035"AN960-816LNAS1149-F0832P10095229A54000000
    1/2"
    0.515"0.875"0.052" to 0.072"MS20002-82591922A30800000
    1/2"
    0.515"0.875"0.059" to 0.067"AN960-816NAS1149-F0863P10095229A55000000
    1/2"
    0.515"2.000"0.099" to 0.119"AN970-8NASM9701095229A96000000
    1/2"
    0.531"1.062"0.074" to 0.121"MS27183-18ASME B18.21.12598032A34600000
    1/2"
    0.562"1.375"0.086" to 0.132"MS27183-19ASME B18.21.11098032A3470000
    9/16"
    0.578"1.062"0.059" to 0.067"AN960-916NAS1149-F0963P5095229A58000000
    9/16"
    0.578"2.188"0.115" to 0.135"AN970-9NASM970595229A9700000
    9/16"
    0.579"0.968"0.052" to 0.072"MS20002-92591922A30900000
    9/16"
    0.594"1.156"0.074" to 0.121"MS27183-20ASME B18.21.12598032A34800000
    5/8"
    0.640"1.188"0.029" to 0.035"AN960-1016LNAS1149-F1032P5095229A6000000
    5/8"
    0.640"1.188"0.059" to 0.067"AN960-1016NAS1149-F1063P5095229A61000000
    5/8"
    0.640"2.375"0.115" to 0.135"AN970-10NASM970595229A56000000
    5/8"
    0.643"1.062"0.052" to 0.072"MS20002-101091922A31100000
    5/8"
    0.656"1.312"0.074" to 0.121"MS27183-21ASME B18.21.12598032A35100000
    5/8"
    0.656"2.125"0.080" to 0.115"MS27183-63598032A34900000
    5/8"
    0.688"1.750"0.108" to 0.160"MS27183-22ASME B18.21.11098032A35200000
    3/4"
    0.765"1.312"0.028" to 0.036"AN960-1216LNAS1149-F1232P5095229A11100000
    3/4"
    0.765"1.312"0.086" to 0.094"AN960-1216LNAS1149-F1290P1095229A11200000
    3/4"
    0.770"1.250"0.052" to 0.072"MS20002-121091922A31200000
    3/4"
    0.812"1.469"0.108" to 0.160"MS27183-23ASME B18.21.11098032A35300000
    3/4"
    0.812"2.000"0.122" to 0.177"MS27183-24ASME B18.21.1598032A35400000
    7/8"
    0.890"1.500"0.028" to 0.036"AN960-1416LNAS1149-F1432P2595229A11500000
    7/8"
    0.890"1.500"0.059" to 0.067"NAS1149-F1463P1095229A11600000
    7/8"
    0.890"1.500"0.086" to 0.094"AN960-1416NAS1149-F1490P1095229A11700000
    7/8"
    0.897"1.437"0.052" to 0.072"MS20002-141091922A31300000
    7/8"
    0.938"1.750"0.108" to 0.160"MS27183-25ASME B18.21.11098032A37100000
    7/8"
    0.938"2.250"0.136" to 0.192"MS27183-26ASME B18.21.1598032A35600000
    1"
    1.015"1.750"0.028" to 0.036"AN960-1616LNAS1149-F1632P1095229A11300000
    1"
    1.015"1.750"0.086" to 0.094"AN960-1616NAS1149-F1690P1095229A11400000
    1"
    1.025"1.625"0.052" to 0.072"MS20002-16591922A31400000
    1"
    1.062"2.000"0.108" to 0.160"MS27183-27ASME B18.21.11098032A35700000
    1"
    1.062"2.500"0.136" to 0.192"MS27183-28ASME B18.21.1198032A3580000
    1 1/8"
    1.250"2.750"0.136" to 0.192"MS27183-29ASME B18.21.1198032A3590000
    1 1/4"
    1.375"3.000"0.136" to 0.192"MS27183-30ASME B18.21.1198032A3610000
    1 3/8"
    1.500"3.250"0.153" to 0.213"MS27183-31ASME B18.21.1198032A3620000
    1 1/2"
    1.625"3.500"0.153" to 0.213"MS27183-32ASME B18.21.1198032A3630000
    1 5/8"
    1.750"3.750"0.153" to 0.213"MS27183-33ASME B18.21.1198032A36400000
    1 3/4"
    1.875"4.000"0.153" to 0.213"MS27183-34ASME B18.21.1198032A36500000
    1 7/8"
    2.000"4.250"0.153" to 0.213"MS27183-35ASME B18.21.1198032A36600000
    2"
    2.125"4.500"0.153" to 0.213"MS27183-36ASME B18.21.1198032A36700000
     
    Copper
    Image of Product. Front orientation. Washers. Mil. Spec. Washers.
    These have the best conductivity of all our metal washers. They're often used to secure electrical connections inside breaker panels and to fasten components on printed circuit boards. They're also the softest of all our metal washers, so they won't damage screws and nuts. However, copper washers aren't as corrosion resistant as brass washers, and will develop a green patina over time.
    Low-Friction Cadmium-Plated Copper—The plating reduces friction between the washer, fastener, and mounting surface to prevent sticking when tightening and loosening. It also creates a barrier against rust.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil.
    Spec.
    Pkg.
    Qty.
    Pkg.
    Low-Friction Cadmium-Plated Copper
    7/16"
    0.443"0.683"0.048" to 0.054"AN901-4C1091818A221000000
    1/2"
    0.505"0.745"0.048" to 0.054"AN901-5C1091818A22300000
    9/16"
    0.568"0.808"0.048" to 0.054"AN901-6C1091818A22400000
    3/4"
    0.755"0.995"0.048" to 0.054"AN901-8C1091818A22500000
    7/8"
    0.880"1.120"0.048" to 0.054"AN901-10C591818A22600000
    1"
    1.068"1.370"0.048" to 0.054"AN901-12C591818A22700000
     

    Mil. Spec. Split Lock Washers

    Image of Product. Front orientation. Lock Washers. Split-Lock Washer, Mil. Spec..
    These washers are manufactured and tested to strict U.S. military standards for material and construction. As you tighten, the uneven ends bite into the nut or screw so it won't loosen due to mild vibration. While they don't hold as tightly 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.
    Corrosion-Resistant Cadmium-Plated Steel—The finish creates a better barrier against rust than zinc plating for use in wet and outdoor environments.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil.
    Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Corrosion-Resistant Cadmium-Plated Steel
    No. 2
    0.088"0.172"0.020"MS35338-39ASME B18.21.15091475A51100000
    No. 4
    0.114"0.209"0.025"MS35338-40ASME B18.21.15091475A5170000
    No. 6
    0.141"0.250"0.031"MS35338-41ASME B18.21.15091475A5230000
    No. 8
    0.167"0.293"0.040"MS35338-42ASME B18.21.15091475A5300000
    No. 10
    0.193"0.334"0.047"MS35338-43ASME B18.21.15091475A5310000
    1/4"
    0.252"0.487"0.062"MS35338-44ASME B18.21.15091475A5350000
    5/16"
    0.314"0.583"0.078"MS35338-45ASME B18.21.15091475A5410000
    3/8"
    0.377"0.680"0.094"MS35338-46ASME B18.21.12591475A5440000
    7/16"
    0.440"0.776"0.109"MS35338-47ASME B18.21.12591475A5480000
    1/2"
    0.502"0.869"0.125"MS35338-48ASME B18.21.11091475A5520000
    9/16"
    0.564"0.965"0.141"MS35338-49ASME B18.21.1591475A5530000
    5/8"
    0.628"1.073"0.156"MS35338-50ASME B18.21.1291475A8200000
     

    Mil. Spec. Tooth Lock Washers

    These washers are manufactured and tested to strict U.S. military standards for material and construction. They resist vibration better than split lock washers to prevent nuts and screws from loosening in applications with constant movement, such as conveyors. Tooth lock washers typically can't be reused because the teeth often get bent when tightened.
    Internal Tooth
    Image of Product. Front orientation. Lock Washers. Tooth Washer, Mil. Spec., Internal Tooth.
    Internal teeth dig into the nut or screw to prevent it from backing out. Unlike external-tooth lock washers, these have a smooth outside edge, so they are less likely to mar your material or snag on objects. However, they don’t grip quite as well. Pair them with fasteners that have small diameters, such as fillister and cheese head screws.
    Corrosion-Resistant Cadmium-Plated Steel—The finish creates a better barrier against rust than zinc plating for use in wet and outdoor environments.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil.
    Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Corrosion-Resistant Cadmium-Plated Steel
    No. 2
    0.089"0.200"0.010" to 0.015"MS35333-35ASME B18.21.1, NASM353332596551A19000000
    No. 4
    0.115"0.270"0.015" to 0.019"MS35333-36ASME B18.21.1, NASM353332596551A2000000
    No. 6
    0.141"0.295"0.017" to 0.021"MS35333-37ASME B18.21.1, NASM353332596551A2100000
    No. 8
    0.168"0.340"0.018" to 0.023"MS35333-38ASME B18.21.1, NASM353332596551A2200000
    No. 10
    0.195"0.381"0.020" to 0.025"MS35333-39ASME B18.21.1, NASM353332596551A2300000
    1/4"
    0.256"0.478"0.023" to 0.028"MS35333-40ASME B18.21.1, NASM353332596551A2400000
    5/16"
    0.332"0.610"0.028" to 0.034"MS35333-41ASME B18.21.1, NASM353332596551A2500000
    3/8"
    0.384"0.692"0.032" to 0.040"MS35333-42ASME B18.21.1, NASM353332596551A26000000
    7/16"
    0.448"0.789"0.032" to 0.040"MS35333-43ASME B18.21.1, NASM353332596551A27000000
    1/2"
    0.512"0.900"0.037" to 0.045"MS35333-44ASME B18.21.1, NASM353332596551A28000000
    5/8"
    0.640"1.071"0.042" to 0.050"MS35333-46ASME B18.21.1, NASM353331096551A2900000
    3/4"
    0.769"1.245"0.047" to 0.055"MS35333-47ASME B18.21.1, NASM353331096551A3000000
    7/8"
    0.894"1.410"0.052" to 0.060"MS35333-48ASME B18.21.1, NASM353331096551A31000000
    1"
    1.019"1.637"0.059" to 0.067"MS35333-49ASME B18.21.1, NASM35333596551A3200000
    1 1/4"
    1.260"1.950"0.059" to 0.067"MS35333-51ASME B18.21.1, NASM35333596551A3300000
     
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