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    149 Products

    ASME Washers

    Also known as Type B washers, these meet ASME sizing standards. They take the pressure off screws and nuts to protect your mounting surface.
    Stainless SteelAbout Stainless Steel
    Image of Product. Front orientation. Washers. ASME 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.
    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.
    High-Strength 17-7 PH Stainless Steel—Some of the strongest stainless steel washers we offer, these are comparable to high-strength Grade 8 steel. They won’t rust in wet and outdoor environments, but they can’t handle the harsh chemicals that 316 stainless steel can.
    For Screw
    Size
    ASME
    Designation
    ID
    OD
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    No. 0
    Narrow0.068"0.125"0.022" to 0.028"ASME B18.21.11092217A31000000
    No. 1
    Narrow0.084"0.156"0.022" to 0.028"ASME B18.21.11092217A1000000
    No. 2
    Narrow0.094"0.188"0.022" to 0.028"ASME B18.21.12592217A35000000
    No. 4
    Narrow0.125"0.250"0.028" to 0.036"ASME B18.21.12592217A36000000
    No. 6
    Narrow0.156"0.312"0.028" to 0.036"ASME B18.21.12592217A4200000
    No. 8
    Narrow0.188"0.375"0.036" to 0.045"ASME B18.21.12592217A43000000
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"ASME B18.21.12592217A4400000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.11092217A4700000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"ASME B18.21.11092217A4900000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.11092217A52000000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"ASME B18.21.1592217A1240000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"ASME B18.21.1592217A5400000
    9/16"
    Narrow0.594"1.125"0.056" to 0.071"ASME B18.21.1592217A1550000
    5/8"
    Narrow0.656"1.250"0.090" to 0.112"ASME B18.21.1192217A1990000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"ASME B18.21.1192217A2240000
    7/8"
    Narrow0.938"1.469"0.090" to 0.112"ASME B18.21.1192217A2360000
    1"
    Narrow1.062"1.750"0.090" to 0.112"ASME B18.21.1192217A2430000
    1 1/8"
    Narrow1.188"2.000"0.090" to 0.112"ASME B18.21.1192217A2560000
    1 1/4"
    Narrow1.313"2.250"0.146" to 0.174"ASME B18.21.1192217A26200000
    1 1/2"
    Narrow1.562"2.750"0.118" to 0.152"192217A70300000
    1 3/4"
    Narrow1.875"3.250"0.118" to 0.152"192217A70400000
    M2.5
    Narrow3.1 mm5.9 mm0.6 mm to 0.9 mmASME B18.22M192217A6110000
    M3
    Narrow3.5 mm6.7 mm0.6 mm to 0.9 mmASME B18.22M192217A6120000
    M4
    Narrow4.7 mm9.8 mm0.8 mm to 1.2 mmASME B18.22M192217A6130000
    M5
    Narrow5.6 mm10.6 mm1.0 mm to 1.4 mmASME B18.22M192217A6140000
    M6
    Narrow6.7 mm12.7 mm1.2 mm to 1.8 mmASME B18.22M192217A6150000
    M10
    Narrow10.9 mm19.8 mm1.6 mm to 2.3 mmASME B18.22M192217A6160000
    M12
    Narrow13.4 mm24.9 mm2.0 mm to 2.8 mmASME B18.22M192217A6170000
    M16
    Narrow17.4 mm31.7 mm2.5 mm to 3.5 mmASME B18.22M192217A6180000
    M20
    Narrow21.9 mm38.4 mm3.0 mm to 4.0 mmASME B18.22M192217A6190000
    M30
    Narrow32.5 mm55.5 mm4.0 mm to 5.1 mmASME B18.22M192217A62100000
     
    Black-Oxide 18-8 Stainless Steel
    No. 6
    Narrow0.156"0.312"0.028" to 0.036"5090474A18800000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"1090474A18900000
    3/4"
    Narrow0.805"1.375"0.050" to 0.080"1090474A10300000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    No. 0
    Narrow0.068"0.125"0.022" to 0.028"ASME B18.21.11092844A1110000
    No. 1
    Narrow0.084"0.156"0.022" to 0.028"ASME B18.21.11092844A1140000
    No. 2
    Narrow0.094"0.188"0.022" to 0.028"ASME B18.21.11092844A1170000
    No. 4
    Narrow0.125"0.250"0.028" to 0.036"ASME B18.21.11092844A1210000
    No. 6
    Narrow0.156"0.312"0.028" to 0.036"ASME B18.21.11092844A1240000
    No. 8
    Narrow0.188"0.375"0.036" to 0.045"ASME B18.21.11092844A1270000
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"ASME B18.21.11092844A1310000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.11092844A1340000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"ASME B18.21.11092844A1370000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.11092844A1410000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"ASME B18.21.1192844A1440000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"ASME B18.21.11092844A1470000
    9/16"
    Narrow0.594"1.125"0.056" to 0.071"ASME B18.21.1192844A1510000
    5/8"
    Narrow0.656"1.250"0.090" to 0.112"ASME B18.21.1192844A1540000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"ASME B18.21.1192844A1570000
    7/8"
    Narrow0.938"1.469"0.090" to 0.112"ASME B18.21.1192844A1610000
    1"
    Narrow1.062"1.750"0.090" to 0.112"ASME B18.21.1192844A1640000
    1 1/8"
    Narrow1.188"2.000"0.090" to 0.112"ASME B18.21.1192844A16700000
    1 1/4"
    Narrow1.313"2.250"0.146" to 0.174"ASME B18.21.1192844A17100000
    M2.5
    Narrow3.1 mm5.9 mm0.6 mm to 0.9 mmASME B18.22M192844A2110000
    M3
    Narrow3.5 mm6.7 mm0.6 mm to 0.9 mmASME B18.22M192844A2120000
    M4
    Narrow4.7 mm9.8 mm0.8 mm to 1.2 mmASME B18.22M192844A2130000
    M5
    Narrow5.6 mm10.6 mm1.0 mm to 1.4 mmASME B18.22M192844A2140000
    M6
    Narrow6.7 mm12.7 mm1.2 mm to 1.8 mmASME B18.22M192844A2150000
    M10
    Narrow10.9 mm19.8 mm1.6 mm to 2.3 mmASME B18.22M192844A2160000
    M12
    Narrow13.4 mm24.9 mm2.0 mm to 2.8 mmASME B18.22M192844A2170000
    M14
    Narrow15.3 mm27.7 mm2.0 mm to 2.8 mmASME B18.22M192844A2180000
    M16
    Narrow17.4 mm31.7 mm2.5 mm to 3.5 mmASME B18.22M192844A2190000
     
    High-Strength 17-7 PH Stainless Steel
    1/4"
    Narrow0.281"0.500"0.051" to 0.080"590474A10400000
     
    Steel
    Image of Product. Front orientation. Washers. ASME Washers.
    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.
    Corrosion-Resistant Galvanized Steel—These washers combine the strength of steel with the rust resistance of stainless steel. They're an economical alternative to 18-8 stainless steel in wet and outdoor environments, but they won't hold up to salt water and chemicals.
    For Fastener Strength Grade/Class—If you require screws or nuts with a specific fastener strength rating, make sure your washer matches the grade or class.
    For Screw
    Size
    ASME
    Designation
    ID
    OD
    Thk.
    For Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    No. 0
    Narrow0.068"0.125"0.022" to 0.028"ASME B18.21.12594744A11000000
    No. 1
    Narrow0.084"0.156"0.022" to 0.028"ASME B18.21.12594744A15700000
    No. 2
    Narrow0.094"0.188"0.022" to 0.028"ASME B18.21.15094744A1500000
    No. 4
    Narrow0.125"0.250"0.028" to 0.036"ASME B18.21.15094744A1550000
    No. 6
    Narrow0.156"0.312"0.028" to 0.036"ASME B18.21.15094744A16000000
    No. 8
    Narrow0.188"0.375"0.036" to 0.045"ASME B18.21.12594744A2200000
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"ASME B18.21.12594744A2250000
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"SAE Grade 5
    ASME B18.21.110094744A51500000
    No. 12
    Narrow0.234"0.438"0.036" to 0.045"ASME B18.21.110094744A51400000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.12594744A24000000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"SAE Grade 5
    ASME B18.21.15094744A51600000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"SAE Grade 8
    ASME B18.21.15094744A50100000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"ASME B18.21.12594744A24500000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"SAE Grade 5
    ASME B18.21.15094744A51900000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12594744A5030000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.12594744A26500000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"SAE Grade 5
    ASME B18.21.15094744A52200000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12594744A50400000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"ASME B18.21.11094744A2870000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"ASME B18.21.1594744A2850000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"SAE Grade 5
    ASME B18.21.12594744A52500000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12594744A50600000
    9/16"
    Narrow0.594"1.125"0.056" to 0.071"ASME B18.21.11094744A3120000
    5/8"
    Narrow0.656"1.250"0.090" to 0.112"ASME B18.21.1594744A3970000
    5/8"
    Narrow0.656"1.250"0.090" to 0.112"SAE Grade 5
    ASME B18.21.11094744A52800000
    5/8"
    Narrow0.656"1.250"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1594744A50800000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"ASME B18.21.1594744A4060000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"SAE Grade 5
    ASME B18.21.11094744A53100000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1594744A51100000
    7/8"
    Narrow0.938"1.469"0.090" to 0.112"ASME B18.21.1594744A41100000
    1"
    Narrow1.062"1.750"0.090" to 0.112"ASME B18.21.1194744A4380000
    1"
    Narrow1.062"1.750"0.090" to 0.112"SAE Grade 5
    ASME B18.21.1594744A53300000
    1"
    Narrow1.062"1.750"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1194744A5130000
    1 1/8"
    Narrow1.188"2.000"0.090" to 0.112"ASME B18.21.1194744A4910000
    1 1/4"
    Narrow1.313"2.250"0.146" to 0.174"ASME B18.21.1194744A60900000
    M3
    Narrow3.5 mm6.8 mm0.6 mm to 0.9 mmASME B18.22M194744A7110000
    M4
    Narrow4.8 mm9.7 mm0.8 mm to 1.2 mmASME B18.22M194744A7120000
    M5
    Narrow5.6 mm10.7 mm1.0 mm to 1.4 mmASME B18.22M194744A7130000
    M6
    Narrow6.7 mm12.7 mm1.2 mm to 1.8 mmASME B18.22M194744A7140000
    M10
    Narrow10.9 mm19.7 mm1.6 mm to 2.3 mmASME B18.22M194744A7150000
    M12
    Narrow13.4 mm24.9 mm2.0 mm to 2.8 mmASME B18.22M194744A7160000
    M16
    Narrow17.4 mm31.7 mm2.5 mm to 3.5 mmASME B18.22M194744A7170000
    M20
    Narrow22.0 mm38.7 mm3.0 mm to 4.0 mmASME B18.22M194744A71800000
    M30
    Narrow32.5 mm55.5 mm4.0 mm to 5.1 mmASME B18.22M194744A71900000
     
    Zinc-Yellow-Chromate-Plated Steel
    No. 8
    Narrow0.188"0.375"0.036" to 0.045"SAE Grade 8
    ASME B18.21.110090474A12500000
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"SAE Grade 8
    ASME B18.21.110090474A12600000
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"SAE Grade 8
    ASME B18.21.15090474A11100000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12590474A1120000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12590474A11300000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12590474A11500000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"SAE Grade 8
    ASME B18.21.12590474A11600000
    3/4"
    Narrow0.812"1.375"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1590474A12100000
    7/8"
    Narrow0.938"1.469"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1590474A12300000
    1"
    Narrow1.062"1.750"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1590474A12400000
    1 1/8"
    Narrow1.188"2.000"0.090" to 0.112"SAE Grade 8
    ASME B18.21.1190474A1340000
    1 1/4"
    Narrow1.312"2.250"0.146" to 0.174"SAE Grade 8
    ASME B18.21.1190474A13500000
    1 1/2"
    Narrow1.562"2.750"0.146" to 0.174"SAE Grade 8
    ASME B18.21.1190474A13600000
    1 3/4"
    Narrow1.875"3.250"0.146" to 0.174"SAE Grade 8
    ASME B18.21.1190474A13700000
     
    Black-Oxide Steel
    No. 10
    Narrow0.203"0.406"0.036" to 0.045"ASME B18.21.110090474A1610000
    No. 12
    Narrow0.234"0.438"0.036" to 0.045"ASME B18.21.110090474A16600000
    7/16"
    Narrow0.469"0.875"0.056" to 0.071"ASME B18.21.12590474A16700000
    1/2"
    Narrow0.531"1.000"0.051" to 0.080"2590474A14100000
    3/4"
    Narrow0.812"1.375"0.080" to 0.115"1090474A14300000
    1"
    Narrow1.062"1.750"0.080" to 0.115"590474A14500000
    1 1/4"
    Narrow1.312"2.250"0.146" to 0.174"ASME B18.21.1190474A1690000
     
    Steel
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.15090474A10600000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"ASME B18.21.15090474A10700000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.15090474A10500000
    3/4"
    Narrow0.812"1.375"0.124" to 0.145"1090474A15800000
    7/8"
    Narrow0.938"1.469"0.090" to 0.112"ASME B18.21.1590474A10900000
    1"
    Narrow1.060"1.750"0.124" to 0.145"1090474A15900000
     
    Corrosion-Resistant Galvanized Steel
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.12590474A14600000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.11090474A14700000
    1/2"
    Narrow0.531"1.000"0.051" to 0.080"2590474A14800000
    3/4"
    Narrow0.812"1.375"0.080" to 0.120"1090474A15100000
    7/8"
    Narrow0.938"1.469"0.080" to 0.120"1090474A15600000
    1"
    Narrow1.062"1.750"0.090" to 0.112"1090474A15200000
     
    AluminumAbout Aluminum
    Image of Product. Front orientation. Washers. ASME Washers.
    One-third the weight of steel, these washers are commonly used in robotics, automation, and other applications that have weight limits. They're an alternative to stainless steel for rust resistance, but aren't as strong.
    For Screw
    Size
    ASME
    Designation
    ID
    OD
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Aluminum
    No. 4
    Narrow0.125"0.250"0.028" to 0.036"ASME B18.21.110090474A17100000
    No. 6
    Narrow0.156"0.312"0.028" to 0.036"ASME B18.21.110090474A17900000
    5/16"
    Narrow0.344"0.625"0.056" to 0.071"ASME B18.21.15090474A1740000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.110090474A18100000
    1/2"
    Narrow0.531"1.000"0.056" to 0.071"ASME B18.21.12590474A17600000
     
    Brass
    Image of Product. Front orientation. Washers. ASME Washers.
    Softer than most metals, brass washers won't damage other fastening components.
    Nickel-Plated Brass—The nickel plating offers better corrosion resistance than plain brass to stand up to solvents, salt water, and chemicals. The plating can wear off over time, so these washers are not recommended for applications that experience a lot of friction or wear.
    For Screw
    Size
    ASME
    Designation
    ID
    OD
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Nickel-Plated Brass
    5/16"
    Narrow0.340"0.625"0.052" to 0.072"ASME B18.21.12590474A182000000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.12590474A18300000
     
    Copper
    Image of Product. Front orientation. Washers. ASME 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
    ASME
    Designation
    ID
    OD
    Thk.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Copper
    1/4"
    Narrow0.281"0.500"0.056" to 0.071"ASME B18.21.12590474A185000000
    3/8"
    Narrow0.406"0.734"0.056" to 0.071"ASME B18.21.12590474A18600000
     
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