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    155 Products

    Mil. Spec. Washers
    3D CAD models available

    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"__NAS620-010000000000000000
    No. 1
    0.078"0.188"0.016" to 0.025"MS27183-1__1000000000000000
    No. 2
    0.089"0.149"0.015" to 0.017"__NAS620-2100000000000000
    No. 2
    0.094"0.250"0.016" to 0.025"MS27183-2ASME B18.21.11000000000000000
    No. 2
    0.099"0.250"0.029" to 0.035"AN960-2NAS1149-FN232P1000000000000000
    No. 3
    0.102"0.180"0.015" to 0.017"__NAS620-3L25000000000000
    No. 3
    0.102"0.180"0.031" to 0.033"__NAS620-3250000000000000
    No. 3
    0.125"0.250"0.017" to 0.028"MS27183-3__1000000000000000
    No. 4
    0.115"0.209"0.015" to 0.017"__NAS620-4L1000000000000000
    No. 4
    0.115"0.209"0.031" to 0.033"__NAS620-41000000000000000
    No. 4
    0.125"0.312"0.014" to 0.018"AN960-4LNAS1149-FN416P1000000000000000
    No. 4
    0.125"0.312"0.025" to 0.040"MS27183-4ASME B18.21.11000000000000000
    No. 4
    0.125"0.312"0.029" to 0.035"AN960-4ASME B18.21.1, NAS1149-FN432P1000000000000000
    No. 4
    0.125"0.375"0.025" to 0.040"MS27183-44__1000000000000000
    No. 5
    0.128"0.238"0.015" to 0.017"__NAS620-5L100000000000000
    No. 5
    0.128"0.238"0.031" to 0.033"__NAS620-52500000000000000
    No. 5
    0.141"0.281"0.025" to 0.040"MS27183-45__1000000000000000
    No. 6
    0.143"0.267"0.015" to 0.017"__NAS620-6L100000000000000
    No. 6
    0.143"0.267"0.031" to 0.033"__NAS620-61000000000000000
    No. 6
    0.149"0.375"0.014" to 0.018"AN960-6LNAS1149-FN616P1000000000000000
    No. 6
    0.149"0.375"0.029" to 0.035"AN960-6NAS1149-FN632P1000000000000000
    No. 6
    0.156"0.250"0.013" to 0.020"MS27183-43__1000000000000000
    No. 6
    0.156"0.312"0.027" to 0.048"MS27183-5__1000000000000000
    No. 6
    0.156"0.375"0.036" to 0.065"MS27183-6ASME B18.21.11000000000000000
    No. 8
    0.169"0.304"0.015" to 0.017"__NAS620-8L2500000000000000
    No. 8
    0.169"0.304"0.031" to 0.033"__NAS620-81000000000000000
    No. 8
    0.174"0.375"0.014" to 0.018"AN960-8LNAS1149-FN816P1000000000000000
    No. 8
    0.174"0.375"0.029" to 0.035"AN960-8NAS1149-FN832P1000000000000000
    No. 8
    0.188"0.375"0.036" to 0.065"MS27183-7__1000000000000000
    No. 8
    0.188"0.438"0.036" to 0.065"MS27183-41ASME B18.21.110000000000000000
    No. 8
    0.188"0.500"0.051" to 0.080"MS27183-46__1000000000000000
    No. 10
    0.195"0.354"0.031" to 0.033"__NAS620-10L100000000000000
    No. 10
    0.195"0.354"0.062" to 0.064"__NAS620-10100000000000000
    No. 10
    0.203"0.438"0.029" to 0.035"AN960-10LNAS1149-F0332P1000000000000000
    No. 10
    0.203"0.438"0.059" to 0.067"AN960-10NAS1149-F0363P1000000000000000
    No. 10
    0.203"0.875"0.053" to 0.073"AN970-3NASM97010000000000000000
    No. 10
    0.219"0.365"0.025" to 0.040"MS27183-47__1000000000000000
    No. 10
    0.219"0.438"0.036" to 0.065"MS27183-8__1000000000000000
    No. 10
    0.219"0.500"0.036" to 0.065"MS27183-42ASME B18.21.110000000000000000
    No. 12
    0.250"0.562"0.025" to 0.040"MS27183-49__1000000000000000
    No. 12
    0.250"0.562"0.051" to 0.080"MS27183-9ASME B18.21.110000000000000000
    No. 12
    0.250"0.625"0.025" to 0.040"MS27183-50__10000000000000000
    No. 12
    0.250"0.938"0.051" to 0.080"MS27183-48__250000000000000
    No. 12
    0.250"1.000"0.051" to 0.080"MS27183-51__250000000000000
    1/4"
    0.255"0.468"0.031" to 0.033"__NAS620-416L1000000000000000
    1/4"
    0.255"0.468"0.062" to 0.064"__NAS620-4161000000000000000
    1/4"
    0.260"0.531"0.052" to 0.072"MS20002-4__2500000000000000
    1/4"
    0.265"0.500"0.029" to 0.035"AN960-416LNAS1149-F0432P1000000000000000
    1/4"
    0.265"0.500"0.059" to 0.067"AN960-416NAS1149-F0463P1000000000000000
    1/4"
    0.265"1.125"0.053" to 0.073"AN970-4NASM9705000000000000000
    1/4"
    0.281"0.625"0.051" to 0.080"MS27183-10ASME B18.21.110000000000000000
    1/4"
    0.281"0.734"0.051" to 0.080"MS27183-52__10000000000000000
    1/4"
    0.312"0.500"0.027" to 0.048"MS27183-54__5000000000000000
    1/4"
    0.312"0.875"0.051" to 0.075"MS27183-53__2500000000000000
    1/4"
    0.313"0.734"0.051" to 0.080"MS27183-11ASME B18.21.15000000000000000
    5/16"
    0.324"0.593"0.052" to 0.072"MS20002-5__2500000000000000
    5/16"
    0.328"0.562"0.029" to 0.035"AN960-516LNAS1149-F0532P1000000000000000
    5/16"
    0.328"0.562"0.059" to 0.067"AN960-516NAS1149-F0563P1000000000000000
    5/16"
    0.328"1.375"0.053" to 0.073"AN970-5NASM9705000000000000000
    5/16"
    0.344"0.688"0.051" to 0.080"MS27183-12ASME B18.21.110000000000000000
    5/16"
    0.375"0.625"0.027" to 0.048"MS27183-56__500000000000000
    5/16"
    0.375"0.734"0.064" to 0.094"MS27183-55__5000000000000000
    5/16"
    0.375"0.875"0.064" to 0.104"MS27183-13ASME B18.21.1500000000000000
    3/8"
    0.385"0.687"0.052" to 0.072"MS20002-6__2500000000000000
    3/8"
    0.390"0.625"0.029" to 0.035"AN960-616LNAS1149-F0632P1000000000000000
    3/8"
    0.390"0.625"0.059" to 0.067"AN960-616NAS1149-F0663P10000000000000000
    3/8"
    0.390"1.625"0.053" to 0.073"AN970-6NASM9702500000000000000
    3/8"
    0.406"0.812"0.051" to 0.080"MS27183-14ASME B18.21.1500000000000000
    3/8"
    0.406"0.875"0.051" to 0.070"MS27183-57__5000000000000000
    3/8"
    0.412"0.625"0.025" to 0.040"MS27183-58__500000000000000
    3/8"
    0.438"0.875"0.051" to 0.080"MS27183-60__5000000000000000
    3/8"
    0.438"1.365"0.064" to 0.104"MS27183-59__1000000000000000
    3/8"
    0.438"1.625"0.051" to 0.104"MS27183-61__1000000000000000
    7/16"
    0.438"1.000"0.064" to 0.104"MS27183-15__5000000000000000
    7/16"
    0.451"0.781"0.052" to 0.072"MS20002-7__2500000000000000
    7/16"
    0.453"0.750"0.029" to 0.035"AN960-716LNAS1149-F0732P10000000000000000
    7/16"
    0.453"0.750"0.059" to 0.067"AN960-716NAS1149-F0763P10000000000000000
    7/16"
    0.453"1.812"0.099" to 0.119"AN970-7NASM9701000000000000000
    7/16"
    0.469"0.734"0.051" to 0.080"MS27183-62__5000000000000000
    7/16"
    0.469"0.922"0.051" to 0.080"MS27183-16ASME B18.21.15000000000000000
    7/16"
    0.500"1.250"0.064" to 0.104"MS27183-17ASME B18.21.15000000000000000
    1/2"
    0.515"0.875"0.029" to 0.035"AN960-816LNAS1149-F0832P10000000000000000
    1/2"
    0.515"0.875"0.052" to 0.072"MS20002-8__2500000000000000
    1/2"
    0.515"0.875"0.059" to 0.067"AN960-816NAS1149-F0863P10000000000000000
    1/2"
    0.515"2.000"0.099" to 0.119"AN970-8NASM9701000000000000000
    1/2"
    0.531"1.062"0.074" to 0.121"MS27183-18ASME B18.21.12500000000000000
    1/2"
    0.562"1.375"0.086" to 0.132"MS27183-19ASME B18.21.1100000000000000
    9/16"
    0.578"1.062"0.059" to 0.067"AN960-916NAS1149-F0963P5000000000000000
    9/16"
    0.578"2.188"0.115" to 0.135"AN970-9NASM97050000000000000
    9/16"
    0.579"0.968"0.052" to 0.072"MS20002-9__2500000000000000
    9/16"
    0.594"1.156"0.074" to 0.121"MS27183-20ASME B18.21.12500000000000000
    5/8"
    0.640"1.188"0.029" to 0.035"AN960-1016LNAS1149-F1032P500000000000000
    5/8"
    0.640"1.188"0.059" to 0.067"AN960-1016NAS1149-F1063P5000000000000000
    5/8"
    0.640"2.375"0.115" to 0.135"AN970-10NASM970500000000000000
    5/8"
    0.643"1.062"0.052" to 0.072"MS20002-10__1000000000000000
    5/8"
    0.656"1.312"0.074" to 0.121"MS27183-21ASME B18.21.12500000000000000
    5/8"
    0.656"2.125"0.080" to 0.115"MS27183-63__500000000000000
    5/8"
    0.688"1.750"0.108" to 0.160"MS27183-22ASME B18.21.11000000000000000
    3/4"
    0.765"1.312"0.028" to 0.036"AN960-1216LNAS1149-F1232P5000000000000000
    3/4"
    0.765"1.312"0.086" to 0.094"AN960-1216LNAS1149-F1290P1000000000000000
    3/4"
    0.770"1.250"0.052" to 0.072"MS20002-12__1000000000000000
    3/4"
    0.812"1.469"0.108" to 0.160"MS27183-23ASME B18.21.11000000000000000
    3/4"
    0.812"2.000"0.122" to 0.177"MS27183-24ASME B18.21.1500000000000000
    7/8"
    0.890"1.500"0.028" to 0.036"AN960-1416LNAS1149-F1432P2500000000000000
    7/8"
    0.890"1.500"0.059" to 0.067"__NAS1149-F1463P1000000000000000
    7/8"
    0.890"1.500"0.086" to 0.094"AN960-1416NAS1149-F1490P1000000000000000
    7/8"
    0.897"1.437"0.052" to 0.072"MS20002-14__1000000000000000
    7/8"
    0.938"1.750"0.108" to 0.160"MS27183-25ASME B18.21.11000000000000000
    7/8"
    0.938"2.250"0.136" to 0.192"MS27183-26ASME B18.21.1500000000000000
    1"
    1.015"1.750"0.028" to 0.036"AN960-1616LNAS1149-F1632P1000000000000000
    1"
    1.015"1.750"0.086" to 0.094"AN960-1616NAS1149-F1690P1000000000000000
    1"
    1.025"1.625"0.052" to 0.072"MS20002-16__500000000000000
    1"
    1.062"2.000"0.108" to 0.160"MS27183-27ASME B18.21.11000000000000000
    1"
    1.062"2.500"0.136" to 0.192"MS27183-28ASME B18.21.110000000000000
    1 1/8"
    1.250"2.750"0.136" to 0.192"MS27183-29ASME B18.21.110000000000000
    1 1/4"
    1.375"3.000"0.136" to 0.192"MS27183-30ASME B18.21.110000000000000
    1 3/8"
    1.500"3.250"0.153" to 0.213"MS27183-31ASME B18.21.110000000000000
    1 1/2"
    1.625"3.500"0.153" to 0.213"MS27183-32ASME B18.21.110000000000000
    1 5/8"
    1.750"3.750"0.153" to 0.213"MS27183-33ASME B18.21.1100000000000000
    1 3/4"
    1.875"4.000"0.153" to 0.213"MS27183-34ASME B18.21.1100000000000000
    1 7/8"
    2.000"4.250"0.153" to 0.213"MS27183-35ASME B18.21.1100000000000000
    2"
    2.125"4.500"0.153" to 0.213"MS27183-36ASME B18.21.1100000000000000
     
    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"AN901-4C10000000000000000
    1/2"
    0.505"0.745"0.048" to 0.054"AN901-5C1000000000000000
    9/16"
    0.568"0.808"0.048" to 0.054"AN901-6C1000000000000000
    3/4"
    0.755"0.995"0.048" to 0.054"AN901-8C1000000000000000
    7/8"
    0.880"1.120"0.048" to 0.054"AN901-10C500000000000000
    1"
    1.068"1.370"0.048" to 0.054"AN901-12C500000000000000
     

    Mil. Spec. Split Lock Washers
    3D CAD models available

    Image of Product. Front orientation. Lock Washers. Mil. Spec., Split-Lock Washer.
    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 B18.21.15000000000000000
    No. 4
    0.114"0.209"0.025"MS35338-40ASME B18.21.1500000000000000
    No. 6
    0.141"0.250"0.031"MS35338-41ASME B18.21.1500000000000000
    No. 8
    0.167"0.293"0.040"MS35338-42ASME B18.21.1500000000000000
    No. 10
    0.193"0.334"0.047"MS35338-43ASME B18.21.1500000000000000
    1/4"
    0.252"0.487"0.062"MS35338-44ASME B18.21.1500000000000000
    5/16"
    0.314"0.583"0.078"MS35338-45ASME B18.21.1500000000000000
    3/8"
    0.377"0.680"0.094"MS35338-46ASME B18.21.1250000000000000
    7/16"
    0.440"0.776"0.109"MS35338-47ASME B18.21.1250000000000000
    1/2"
    0.502"0.869"0.125"MS35338-48ASME B18.21.1100000000000000
    9/16"
    0.564"0.965"0.141"MS35338-49ASME B18.21.150000000000000
    5/8"
    0.628"1.073"0.156"MS35338-50ASME B18.21.120000000000000
     

    Mil. Spec. Tooth Lock Washers
    3D CAD models available

    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. Mil. Spec., Tooth Washer, 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, NASM353332500000000000000
    No. 4
    0.115"0.270"0.015" to 0.019"MS35333-36ASME B18.21.1, NASM35333250000000000000
    No. 6
    0.141"0.295"0.017" to 0.021"MS35333-37ASME B18.21.1, NASM35333250000000000000
    No. 8
    0.168"0.340"0.018" to 0.023"MS35333-38ASME B18.21.1, NASM35333250000000000000
    No. 10
    0.195"0.381"0.020" to 0.025"MS35333-39ASME B18.21.1, NASM35333250000000000000
    1/4"
    0.256"0.478"0.023" to 0.028"MS35333-40ASME B18.21.1, NASM35333250000000000000
    5/16"
    0.332"0.610"0.028" to 0.034"MS35333-41ASME B18.21.1, NASM35333250000000000000
    3/8"
    0.384"0.692"0.032" to 0.040"MS35333-42ASME B18.21.1, NASM353332500000000000000
    7/16"
    0.448"0.789"0.032" to 0.040"MS35333-43ASME B18.21.1, NASM353332500000000000000
    1/2"
    0.512"0.900"0.037" to 0.045"MS35333-44ASME B18.21.1, NASM353332500000000000000
    5/8"
    0.640"1.071"0.042" to 0.050"MS35333-46ASME B18.21.1, NASM35333100000000000000
    3/4"
    0.769"1.245"0.047" to 0.055"MS35333-47ASME B18.21.1, NASM35333100000000000000
    7/8"
    0.894"1.410"0.052" to 0.060"MS35333-48ASME B18.21.1, NASM353331000000000000000
    1"
    1.019"1.637"0.059" to 0.067"MS35333-49ASME B18.21.1, NASM3533350000000000000
    1 1/4"
    1.260"1.950"0.059" to 0.067"MS35333-51ASME B18.21.1, NASM3533350000000000000
     
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