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    150 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.
    Stainless SteelAbout Stainless Steel
    Image of Product. Front orientation. Washers. Mil. Spec. Washers.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these washers resist rust. However, they won'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 resist rust in wet and outdoor environments, but won't hold up to harsh chemicals as well as 316 stainless steel.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil. Spec.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    No. 1
    0.078"0.188"0.016" to 0.025"MS15795-801NASM1579550098019A395000000
    No. 2
    0.094"0.250"0.016" to 0.025"MS15795-802ASME B18.21.1, NASM1579550098019A30000000
    No. 4
    0.125"0.250"0.017" to 0.028"MS15795-803NASM1579550098019A30900000
    No. 4
    0.125"0.312"0.025" to 0.040"MS15795-804ASME B18.21.1, NASM1579550098019A31000000
    No. 6
    0.156"0.312"0.027" to 0.048"MS15795-805NASM1579525098019A31400000
    No. 6
    0.156"0.375"0.036" to 0.065"MS15795-806ASME B18.21.1, NASM1579525098019A31500000
    No. 8
    0.188"0.375"0.036" to 0.065"MS15795-807NASM1579525098019A32500000
    No. 8
    0.188"0.438"0.036" to 0.065"MS15795-841ASME B18.21.1, NASM1579512598019A32600000
    No. 10
    0.219"0.438"0.036" to 0.065"MS15795-808NASM1579525098019A33000000
    No. 10
    0.219"0.500"0.036" to 0.065"MS15795-842ASME B18.21.1, NASM1579510098019A33300000
    No. 12
    0.250"0.562"0.051" to 0.080"MS15795-809ASME B18.21.1, NASM1579510098019A33500000
    1/4"
    0.281"0.625"0.051" to 0.080"MS15795-810ASME B18.21.1, NASM157955098019A35500000
    1/4"
    0.312"0.734"0.051" to 0.080"MS15795-811ASME B18.21.1, NASM157952598019A36000000
    5/16"
    0.344"0.688"0.051" to 0.080"MS15795-812ASME B18.21.1, NASM157952598019A3850000
    5/16"
    0.375"0.875"0.064" to 0.104"MS15795-813NASM157952598019A39000000
    3/8"
    0.406"0.812"0.051" to 0.080"MS15795-814ASME B18.21.1, NASM157955098019A39900000
    3/8"
    0.438"1.000"0.064" to 0.104"MS15795-815ASME B18.21.1, NASM157951098019A5000000
    7/16"
    0.469"0.922"0.051" to 0.080"MS15795-816ASME B18.21.1, NASM157952598019A50200000
    7/16"
    0.500"1.250"0.064" to 0.104"MS15795-817ASME B18.21.1, NASM157951098019A50500000
    1/2"
    0.531"1.062"0.074" to 0.121"MS15795-818ASME B18.21.1, NASM157951098019A50900000
    1/2"
    0.562"1.375"0.086" to 0.132"MS15795-819ASME B18.21.1, NASM157951098019A51000000
    5/8"
    0.656"1.312"0.074" to 0.121"MS15795-820ASME B18.21.1, NASM157951098019A51400000
    5/8"
    0.688"1.750"0.108" to 0.160"MS15795-821ASME B18.21.1, NASM15795598019A51500000
    3/4"
    0.812"1.469"0.108" to 0.160"MS15795-822ASME B18.21.1, NASM15795598019A51900000
    3/4"
    0.812"2.000"0.122" to 0.177"MS15795-823ASME B18.21.1, NASM15795598019A52000000
    7/8"
    0.938"1.750"0.108" to 0.160"MS15795-824ASME B18.21.1, NASM15795598019A52400000
    7/8"
    0.938"2.250"0.136" to 0.192"MS15795-825ASME B18.21.1, NASM15795198019A5250000
    1"
    1.062"2.000"0.108" to 0.160"MS15795-826ASME B18.21.1, NASM15795198019A5290000
    1"
    1.062"2.500"0.136" to 0.192"MS15795-827ASME B18.21.1, NASM15795198019A5300000
     
    Black-Oxide 18-8 Stainless Steel
    No. 1
    0.078"0.188"0.016" to 0.025"MS15795-801BNASM1579510090618A11100000
    No. 2
    0.094"0.218"0.018" to 0.022"MS15795-844BNASM1579510090618A11300000
    No. 2
    0.094"0.250"0.016" to 0.025"MS15795-802BASME B18.21.1, NASM1579510090618A11200000
    No. 4
    0.125"0.250"0.017" to 0.028"MS15795-803BNASM1579510090618A2000000
    No. 4
    0.125"0.312"0.025" to 0.040"MS15795-804BASME B18.21.1, NASM1579510090618A11400000
    No. 6
    0.156"0.312"0.027" to 0.048"MS15795-805BNASM1579510090618A3000000
    No. 6
    0.156"0.375"0.036" to 0.065"MS15795-806BASME B18.21.1, NASM1579510090618A11500000
    No. 6
    0.172"0.281"0.029" to 0.039"MS15795-845BNASM1579510090618A11600000
    No. 6
    0.172"0.312"0.029" to 0.039"MS15795-856BNASM1579510090618A11700000
    No. 8
    0.188"0.375"0.036" to 0.065"MS15795-807BNASM1579510090618A40000000
    No. 8
    0.188"0.438"0.036" to 0.065"MS15795-841BASME B18.21.1, NASM1579510090618A11800000
    No. 10
    0.203"0.375"0.019" to 0.021"MS15795-846BNASM1579510090618A11900000
    No. 10
    0.203"0.562"0.029" to 0.035"MS15795-847BNASM1579510090618A12200000
    No. 10
    0.203"0.562"0.057" to 0.069"MS15795-848BNASM157955090618A12300000
    No. 10
    0.203"0.625"0.035" to 0.045"MS15795-849BNASM157955090618A1240000
    No. 10
    0.203"0.734"0.025" to 0.045"MS15795-857BNASM157955090618A12500000
    No. 10
    0.203"1.062"0.017" to 0.023"MS15795-850BNASM157951090618A12600000
    No. 10
    0.219"0.438"0.036" to 0.065"MS15795-808BNASM1579510090618A50000000
    No. 10
    0.219"0.500"0.036" to 0.065"MS15795-842BASME B18.21.1, NASM1579510090618A12100000
    1/4"
    0.250"0.562"0.051" to 0.080"MS15795-809BNASM1579510090618A12900000
    1/4"
    0.250"0.688"0.065" to 0.075"MS15795-851BNASM157952590618A13200000
    1/4"
    0.266"0.458"0.028" to 0.046"MS15795-858BNASM1579510090618A12800000
    1/4"
    0.266"0.625"0.026" to 0.036"MS15795-852BNASM1579510090618A13100000
    1/4"
    0.266"0.688"0.046" to 0.054"MS15795-853BNASM157955090618A13300000
    1/4"
    0.281"0.625"0.051" to 0.080"MS15795-810BASME B18.21.1, NASM157955090618A60000000
    1/4"
    0.296"0.438"0.029" to 0.035"MS15795-854BNASM1579510090618A12700000
    5/16"
    0.312"0.734"0.051" to 0.080"MS15795-811BNASM157955090618A13400000
    5/16"
    0.344"0.688"0.051" to 0.080"MS15795-812BASME B18.21.1, NASM157955090618A70000000
    3/8"
    0.375"0.875"0.064" to 0.104"MS15795-813BNASM157952590618A13500000
    3/8"
    0.406"0.812"0.051" to 0.080"MS15795-814BASME B18.21.1, NASM157955090618A80000000
    7/16"
    0.438"1.000"0.064" to 0.104"MS15795-815BNASM157952590618A13600000
    7/16"
    0.469"0.922"0.051" to 0.080"MS15795-816BASME B18.21.1, NASM157952590618A13700000
    1/2"
    0.500"1.250"0.064" to 0.104"MS15795-817BNASM157951090618A13800000
    1/2"
    0.531"1.062"0.074" to 0.121"MS15795-818BASME B18.21.1, NASM157951090618A90000000
    1/2"
    0.531"1.250"0.090" to 0.112"MS15795-855BNASM157951090618A13900000
    1/2"
    0.562"1.375"0.086" to 0.132"MS15795-819BASME B18.21.1, NASM15795590618A14100000
    9/16"
    0.594"1.469"0.090" to 0.112"MS15795-843BNASM15795590618A14200000
    5/8"
    0.656"1.312"0.074" to 0.121"MS15795-820BASME B18.21.1, NASM15795590618A14300000
    3/4"
    0.812"1.469"0.108" to 0.160"MS15795-822BASME B18.21.1, NASM15795590618A14400000
    3/4"
    0.812"2.000"0.122" to 0.177"MS15795-823BASME B18.21.1, NASM15795590618A14500000
    7/8"
    0.938"1.750"0.108" to 0.160"MS15795-824BASME B18.21.1, NASM15795590618A14600000
    7/8"
    0.938"2.250"0.136" to 0.192"MS15795-825BASME B18.21.1, NASM15795190618A1470000
    1"
    1.062"2.000"0.108" to 0.160"MS15795-826BASME B18.21.1, NASM15795190618A1480000
    1"
    1.062"2.500"0.136" to 0.192"MS15795-827BASME B18.21.1, NASM15795190618A1490000
    1 1/8"
    1.250"2.750"0.136" to 0.192"MS15795-828BASME B18.21.1, NASM15795190618A15100000
     
    Brass
    Image of Product. Front orientation. Washers. Mil. Spec. Washers.
    Softer than most metals, brass washers won't damage other fastening components.
    Black-Oxide Brass—Typically chosen for their appearance, these washers have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to salt water and harsh chemicals.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil. Spec.
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Brass
    No. 2
    0.094"0.250"0.016" to 0.025"MS15795-9021098102A11200000
    No. 4
    0.125"0.250"0.017" to 0.028"MS15795-9031098102A1130000
    No. 4
    0.125"0.312"0.025" to 0.040"MS15795-9041098102A11400000
    No. 5
    0.141"0.312"0.024" to 0.032"MS15795-9441098102A11500000
    No. 6
    0.156"0.312"0.027" to 0.048"MS15795-9051098102A11700000
    No. 6
    0.156"0.375"0.036" to 0.065"MS15795-9061098102A11800000
    No. 8
    0.188"0.375"0.036" to 0.065"MS15795-9071098102A11900000
    No. 8
    0.188"0.438"0.036" to 0.065"MS15795-9411098102A12100000
    No. 10
    0.203"0.406"0.036" to 0.045"MS15795-9461098102A12200000
    No. 10
    0.219"0.438"0.036" to 0.065"MS15795-9081098102A12300000
    No. 10
    0.219"0.469"0.036" to 0.065"MS15795-9471098102A12400000
    No. 12
    0.250"0.438"0.013" to 0.020"MS15795-9481098102A12600000
    No. 12
    0.250"0.500"0.036" to 0.065"MS15795-9491098102A12700000
    No. 12
    0.250"0.562"0.051" to 0.080"MS15795-9091098102A12800000
    1/4"
    0.281"0.625"0.051" to 0.080"MS15795-9101098102A12900000
    1/4"
    0.312"0.734"0.051" to 0.080"MS15795-9111098102A13100000
    5/16"
    0.344"0.688"0.051" to 0.080"MS15795-9121098102A13200000
    5/16"
    0.375"0.875"0.035" to 0.045"MS15795-9511098102A13300000
    5/16"
    0.375"0.875"0.064" to 0.104"MS15795-9131098102A13400000
    3/8"
    0.406"0.688"0.024" to 0.034"MS15795-9521098102A13500000
    3/8"
    0.406"0.812"0.051" to 0.080"MS15795-9141098102A13600000
    3/8"
    0.438"1.000"0.064" to 0.104"MS15795-915198102A1370000
    7/16"
    0.469"0.922"0.051" to 0.080"MS15795-916198102A1380000
    7/16"
    0.500"1.250"0.064" to 0.104"MS15795-917198102A1390000
    1/2"
    0.531"1.062"0.074" to 0.121"MS15795-918198102A1410000
    5/8"
    0.688"1.750"0.108" to 0.160"MS15795-921198102A14600000
    3/4"
    0.812"1.469"0.108" to 0.160"MS15795-922198102A1470000
    1"
    1.062"2.000"0.108" to 0.160"MS15795-926198102A15100000
     
    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.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil. Spec.
    Pkg.
    Qty.
    Pkg.
    Copper
    No. 1
    0.078"0.188"0.016" to 0.025"MS15795-50110097565A111000000
    No. 2
    0.094"0.250"0.016" to 0.025"MS15795-50210097565A11200000
    No. 4
    0.125"0.250"0.017" to 0.028"MS15795-50310097565A11300000
    No. 4
    0.125"0.312"0.025" to 0.040"MS15795-5045097565A11400000
    No. 5
    0.141"0.406"0.035" to 0.045"MS15795-5445097565A11500000
    No. 6
    0.156"0.312"0.027" to 0.048"MS15795-5055097565A11600000
    No. 6
    0.156"0.375"0.036" to 0.065"MS15795-5065097565A11700000
    No. 8
    0.188"0.375"0.036" to 0.065"MS15795-5075097565A11800000
    No. 8
    0.188"0.438"0.036" to 0.065"MS15795-5415097565A11900000
    No. 10
    0.219"0.438"0.027" to 0.048"MS15795-5455097565A12100000
    No. 10
    0.219"0.438"0.036" to 0.065"MS15795-5085097565A12200000
    No. 10
    0.219"0.500"0.036" to 0.065"MS15795-5425097565A12300000
    No. 12
    0.250"0.562"0.051" to 0.080"MS15795-5092597565A12400000
    1/4"
    0.281"0.625"0.051" to 0.080"MS15795-5102597565A12500000
    1/4"
    0.312"0.734"0.051" to 0.080"MS15795-5112097565A12600000
    5/16"
    0.344"0.562"0.027" to 0.048"MS15795-5475097565A12700000
    5/16"
    0.344"0.688"0.051" to 0.080"MS15795-5122097565A12800000
    5/16"
    0.375"0.875"0.064" to 0.104"MS15795-513597565A12900000
    3/8"
    0.406"0.812"0.051" to 0.080"MS15795-5141097565A13100000
    3/8"
    0.438"1.000"0.064" to 0.104"MS15795-515597565A13200000
    7/16"
    0.469"0.922"0.051" to 0.080"MS15795-5161097565A13300000
    7/16"
    0.500"1.250"0.064" to 0.104"MS15795-517597565A13400000
    1/2"
    0.531"1.062"0.074" to 0.121"MS15795-518597565A13500000
    1/2"
    0.562"1.375"0.086" to 0.132"MS15795-519597565A13600000
    9/16"
    0.594"1.469"0.090" to 0.112"MS15795-543197565A13700000
    9/16"
    0.625"1.000"0.027" to 0.048"MS15795-5521097565A13900000
    5/8"
    0.656"1.312"0.074" to 0.121"MS15795-520597565A14100000
    3/4"
    0.812"1.469"0.108" to 0.160"MS15795-522197565A14300000
    7/8"
    0.938"1.750"0.108" to 0.160"MS15795-524197565A14400000
    1"
    1.062"2.000"0.108" to 0.160"MS15795-526197565A14500000
     
    Nickel
    Image of Product. Front orientation. Washers. Mil. Spec. Washers.
    Super-Corrosion-Resistant 400 Nickel—Commonly found in the oil and gas industries, these washers have similar strength to 316 stainless steel, but are more corrosion resistant to stand up to salt water and harsh acids. They're often used as a high-strength alternative to titanium. Also known as Monel.
    For Screw
    Size
    ID
    OD
    Thk.
    Mil. Spec.
    Pkg.
    Qty.
    Pkg.
    Super-Corrosion-Resistant 400 Nickel
    No. 1
    0.078"0.188"0.016" to 0.025"MS15795-4012597168A111000000
    No. 2
    0.094"0.250"0.016" to 0.025"MS15795-4022597168A11200000
    No. 4
    0.125"0.250"0.017" to 0.028"MS15795-4032597168A11300000
    No. 4
    0.125"0.312"0.025" to 0.040"MS15795-4042597168A11400000
    No. 6
    0.156"0.312"0.027" to 0.048"MS15795-4052597168A11500000
    No. 8
    0.188"0.375"0.036" to 0.065"MS15795-4071097168A11700000
    No. 8
    0.188"0.438"0.036" to 0.065"MS15795-4411097168A13700000
    No. 10
    0.219"0.438"0.036" to 0.065"MS15795-4081097168A11800000
    No. 10
    0.219"0.500"0.036" to 0.065"MS15795-4421097168A13800000
    1/4"
    0.281"0.625"0.051" to 0.080"MS15795-410597168A12100000
    1/4"
    0.312"0.734"0.051" to 0.080"MS15795-411597168A12200000
    5/16"
    0.344"0.688"0.051" to 0.080"MS15795-412597168A12300000
    3/8"
    0.406"0.625"0.051" to 0.080"MS15795-448597168A14100000
    3/8"
    0.406"0.812"0.051" to 0.080"MS15795-414197168A1250000
    7/16"
    0.500"0.875"0.058" to 0.070"MS15795-449197168A1420000
    1/2"
    0.531"1.062"0.074" to 0.121"MS15795-418197168A12900000
    5/8"
    0.688"1.750"0.108" to 0.160"MS15795-421197168A13300000
    3/4"
    0.812"1.469"0.108" to 0.160"MS15795-422197168A13400000
     
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