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    128 Products

    Undersized Washers

    These washers distribute pressure evenly under fasteners with narrow heads, such as cheese and socket head screws. They have smaller diameters than general purpose washers of the same screw size.
    Stainless SteelAbout Stainless Steel
    Image of Product. Front orientation. Washers. Undersized 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.
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M1.6
    		1.73.50.3 to 0.4DIN 43310000000000000000
    M2
    		2.24.50.2 to 0.4DIN 433, ISO 70921000000000000000
    M2.5
    		2.75.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M3
    		3.26.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M3.5
    		3.77.00.5 to 0.6DIN 4331000000000000000
    M4
    		4.38.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M5
    		5.39.00.9 to 1.1DIN 433, ISO 70921000000000000000
    M6
    		6.411.01.4 to 1.8DIN 433, ISO 70921000000000000000
    M8
    		8.415.01.4 to 1.8DIN 433, ISO 70921000000000000000
    M10
    		10.518.01.4 to 1.8DIN 433, ISO 709210000000000000000
    M12
    		13.020.01.8 to 2.2DIN 433, ISO 709210000000000000000
    M14
    		15.024.02.3 to 2.7DIN 433, ISO 70922500000000000000
    M16
    		17.028.02.3 to 2.7DIN 433, ISO 70922500000000000000
    M18
    		19.030.02.3 to 2.7DIN 43310000000000000
    M20
    		21.034.02.7 to 3.3DIN 433, ISO 7092100000000000000
    M24
    		25.039.03.7 to 4.3DIN 43310000000000000
     
    Black-Oxide 18-8 Stainless Steel
    M3
    		3.26.00.5 to 0.6DIN 4331000000000000000
    M4
    		4.38.00.5 to 0.6DIN 43310000000000000000
    M5
    		5.39.00.9 to 1.1DIN 43310000000000000000
    M6
    		6.411.01.4 to 1.8DIN 43310000000000000000
    M8
    		8.415.01.4 to 1.8DIN 4335000000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
    M2
    		2.24.50.3 to 0.4DIN 433250000000000000
    M2.5
    		2.75.00.5 to 0.6DIN 4331000000000000000
    M3
    		3.26.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M4
    		4.38.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M5
    		5.39.00.9 to 1.1DIN 433, ISO 70921000000000000000
    M6
    		6.411.01.4 to 1.8DIN 433, ISO 70921000000000000000
    M8
    		8.415.01.4 to 1.8DIN 433, ISO 7092500000000000000
    M10
    		10.518.01.4 to 1.8DIN 433, ISO 7092500000000000000
    M12
    		13.020.01.8 to 2.2DIN 433, ISO 7092250000000000000
    M14
    		15.024.02.3 to 2.7DIN 4331000000000000000
    M16
    		17.028.02.3 to 2.7DIN 433, ISO 7092100000000000000
    M20
    		21.034.02.7 to 3.3DIN 433, ISO 70921000000000000000
    M24
    		25.039.03.7 to 4.3DIN 43310000000000000
     
    Steel
    Image of Product. Front orientation. Washers. Undersized 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.
    Blue-Dyed Steel—These metric-sized washers have a distinctive blue color, so you can easily tell them apart from inch washers. The coating provides only minimal corrosion resistance, so these washers are 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.
    Black Super-Corrosion-Resistant-Coated Steel—Combines a finished appearance with the rust resistance of 316 stainless steel. The coating has been tested to extreme standards, including 1,000 hours of salt spray resistance, to hold up in wet and outdoor environments. Also known as black luster.
    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
    ID,
    mm
    OD,
    mm
    Thk., mm
    For Fastener Strength
    Grade/Class
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M2
    		2.24.50.2 to 0.4—DIN 433, ISO 709210000000000000000
    M2.5
    		2.75.00.4 to 0.6—DIN 433, ISO 70921000000000000000
    M3
    		3.26.00.4 to 0.6—DIN 433, ISO 70921000000000000000
    M3
    		3.26.00.5 to 0.6ISO Class 8.8
    		DIN 4331000000000000000
    M3
    		3.26.00.5 to 0.6ISO Class 10.9
    		DIN 4331000000000000000
    M3.5
    		3.77.00.4 to 0.6—DIN 433, ISO 70921000000000000000
    M4
    		4.38.00.4 to 0.6—DIN 433, ISO 70921000000000000000
    M4
    		4.38.00.5 to 0.6ISO Class 8.8
    		DIN 4331000000000000000
    M4
    		4.38.00.5 to 0.6ISO Class 10.9
    		DIN 43310000000000000000
    M5
    		5.39.00.9 to 1.1—DIN 433, ISO 70921000000000000000
    M5
    		5.39.00.9 to 1.1ISO Class 8.8
    		DIN 4331000000000000000
    M5
    		5.39.00.9 to 1.1ISO Class 10.9
    		DIN 43310000000000000000
    M6
    		6.411.01.4 to 1.8—DIN 433, ISO 70921000000000000000
    M6
    		6.411.01.4 to 1.8ISO Class 8.8
    		DIN 43310000000000000000
    M6
    		6.411.01.4 to 1.8ISO Class 10.9
    		DIN 4335000000000000000
    M8
    		8.415.01.4 to 1.8—DIN 433, ISO 70921000000000000000
    M8
    		8.415.01.4 to 1.8ISO Class 8.8
    		DIN 4335000000000000000
    M8
    		8.415.01.4 to 1.8ISO Class 10.9
    		DIN 433250000000000000
    M10
    		10.518.01.4 to 1.8—DIN 433, ISO 709210000000000000000
    M10
    		10.518.01.4 to 1.8ISO Class 8.8
    		DIN 4335000000000000000
    M10
    		10.518.01.4 to 1.8ISO Class 10.9
    		DIN 433250000000000000
    M12
    		13.020.01.8 to 2.2—DIN 433, ISO 709210000000000000000
    M12
    		13.020.01.8 to 2.2ISO Class 8.8
    		DIN 4332500000000000000
    M12
    		13.020.01.8 to 2.2ISO Class 10.9
    		DIN 4332500000000000000
    M14
    		15.024.02.3 to 2.7—DIN 433, ISO 70925000000000000000
    M14
    		15.024.02.3 to 2.7ISO Class 8.8
    		DIN 433100000000000000
    M14
    		15.024.02.3 to 2.7ISO Class 10.9
    		DIN 4331000000000000000
    M16
    		17.028.02.3 to 2.7—DIN 433, ISO 7092250000000000000
    M16
    		17.028.02.3 to 2.7ISO Class 8.8
    		DIN 4331000000000000000
    M16
    		17.028.02.3 to 2.7ISO Class 10.9
    		DIN 433100000000000000
    M18
    		19.030.02.3 to 2.7—DIN 433, ISO 70922500000000000000
    M20
    		21.034.02.7 to 3.3—DIN 433, ISO 7092100000000000000
    M20
    		21.034.02.7 to 3.3ISO Class 8.8
    		DIN 433500000000000000
    M20
    		21.034.02.7 to 3.3ISO Class 10.9
    		DIN 43350000000000000
    M24
    		25.039.03.7 to 4.3—DIN 433, ISO 709250000000000000
    M24
    		25.039.03.7 to 4.3ISO Class 8.8
    		DIN 43310000000000000
    M24
    		25.039.03.7 to 4.3ISO Class 10.9
    		DIN 43310000000000000
     
    Zinc-Yellow-Chromate-Plated Steel
    M4
    		4.38.00.5 to 0.6ISO Class 10.9
    		DIN 43310000000000000000
    M5
    		5.39.00.9 to 1.1ISO Class 10.9
    		DIN 43310000000000000000
    M6
    		6.411.01.4 to 1.8ISO Class 10.9
    		DIN 4335000000000000000
    M8
    		8.415.01.4 to 1.8ISO Class 10.9
    		DIN 433250000000000000
    M10
    		10.518.01.4 to 1.8ISO Class 10.9
    		DIN 433250000000000000
    M12
    		13.020.01.8 to 2.2ISO Class 10.9
    		DIN 4332500000000000000
    M14
    		15.024.02.3 to 2.7ISO Class 10.9
    		DIN 4331000000000000000
    M16
    		17.028.02.3 to 2.7ISO Class 10.9
    		DIN 4331000000000000000
    M20
    		21.034.02.7 to 3.3ISO Class 10.9
    		DIN 433500000000000000
     
    Black-Oxide Steel
    M3
    		3.26.00.5 to 0.6—DIN 433100000000000000
    M5
    		5.39.00.9 to 1.1—DIN 4335000000000000000
    M8
    		8.415.01.4 to 1.8—DIN 4335000000000000000
    M10
    		10.518.01.4 to 1.8—DIN 433500000000000000
    M12
    		13.020.01.8 to 2.2—DIN 433250000000000000
    M20
    		21.034.02.7 to 3.3—DIN 433100000000000000
     
    Blue-Dyed Steel
    M3
    		3.06.00.4 to 0.6—DIN 433200000000000000
    M4
    		4.08.00.4 to 0.6—DIN 433200000000000000
    M5
    		5.09.00.9 to 1.1—DIN 433200000000000000
    M8
    		8.015.01.4 to 1.8—DIN 433200000000000000
     
    Steel
    M5
    		5.39.00.9 to 1.1—DIN 4331000000000000000
    M6
    		6.411.01.4 to 1.8—DIN 4331000000000000000
    M8
    		8.415.01.4 to 1.8—DIN 4331000000000000000
    M10
    		10.518.01.4 to 1.8—DIN 4331000000000000000
    M12
    		13.020.02.3 to 2.7—DIN 43310000000000000000
    M20
    		21.034.02.7 to 3.3—DIN 4331000000000000000
    M24
    		25.039.03.7 to 4.3—DIN 433500000000000000
     
    Corrosion-Resistant Galvanized Steel
    M6
    		6.411.01.4 to 1.8—DIN 433100000000000000
    M8
    		8.415.01.4 to 1.8—DIN 433100000000000000
    M10
    		10.518.01.4 to 1.8—DIN 433100000000000000
     
    Black Super-Corrosion-Resistant-Coated Steel
    M6
    		6.411.01.4 to 1.8—DIN 433, ISO 70921000000000000000
    M8
    		8.415.01.4 to 1.8—DIN 433, ISO 70921000000000000000
    M10
    		10.518.01.4 to 1.8—DIN 433, ISO 70921000000000000000
    M12
    		13.020.01.8 to 2.2—DIN 433, ISO 70921000000000000000
     
    Brass
    Image of Product. Front orientation. Washers. Undersized Washers.
    Softer than most metals, brass washers won't damage other fastening components.
    Brass—With a warm, polished look, these washers are often chosen for their appearance. Similar to 18-8 stainless steel, brass is corrosion resistant enough to stand up to wet environments.
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Brass
    M1.6
    		1.73.50.2 to 0.4DIN 433, ISO 709210000000000000000
    M2
    		2.24.50.2 to 0.4DIN 433, ISO 70921000000000000000
    M2.5
    		2.75.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M3
    		3.26.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M4
    		4.38.00.4 to 0.6DIN 433, ISO 70921000000000000000
    M5
    		5.39.00.9 to 1.1DIN 433, ISO 70921000000000000000
    M6
    		6.411.01.4 to 1.8DIN 433, ISO 7092500000000000000
    M8
    		8.415.01.4 to 1.8DIN 433, ISO 7092250000000000000
    M10
    		10.518.01.4 to 1.8DIN 433, ISO 70922500000000000000
    M12
    		13.020.01.8 to 2.2DIN 433, ISO 7092100000000000000
    M14
    		15.024.02.3 to 2.8DIN 433, ISO 70921000000000000000
    M16
    		16.028.02.3 to 2.7DIN 433, ISO 70921000000000000000
    M20
    		21.034.02.7 to 3.3DIN 433, ISO 709210000000000000
     
    Copper
    Image of Product. Front orientation. Washers. Undersized 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,
    mm
    OD,
    mm
    Thk., mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Copper
    M6
    		6.411.01.4 to 1.8DIN 43325000000000000000
    M8
    		8.415.01.4 to 1.8DIN 4331000000000000000
     

    Plastic Washers

    Image of Product. Front orientation. Washers. Plastic Washers.
    All of these washers are lightweight, nonconductive, and naturally rust resistant. They are commonly used in electronics and automation applications to take the pressure off screws and nuts and protect mounting surfaces.
    Nylon—The most popular plastic washers, these are strong, durable, and economical. Nylon will swell and weaken when exposed to moisture, so these washers are best for dry environments.
    Clear Impact-Resistant Polycarbonate—Withstand bumps and vibration without cracking or denting. These washers are also clear to be less noticeable in your assembly.
    Temp.
    Range, ° F
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Min.
    Max.
    Specs.
    Met
    Color
    Pkg.
    Qty.
    Pkg.
    Nylon
    M1.6
    		1.73.50.3 to 0.5-40220DIN 433Off-White2500000000000000
    M3
    		3.26.00.5 to 0.7-40220DIN 433Off-White250000000000000
    M3.5
    		3.77.00.4 to 0.6-40220DIN 433Off-White2500000000000000
    M5
    		5.39.00.8 to 1.2-40220DIN 433Off-White2500000000000000
    M8
    		8.415.01.5 to 1.7-40220DIN 433Off-White2500000000000000
    M10
    		10.518.01.4 to 1.8-40220DIN 433Off-White2500000000000000
    M12
    		13.020.01.8 to 2.2-40220DIN 433Off-White100000000000000
     
    Clear Impact-Resistant Polycarbonate
    M2.5
    		2.75.00.5 to 0.6-40220DIN 433Clear250000000000000
    M3
    		3.26.00.5 to 0.6-40220DIN 433Clear250000000000000
     
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