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    53 Products

    Undersized Washers

    Image of Product. Front orientation. Washers. 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
    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.
    Highly 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.
    Material Certificate—Washers include a report with a traceable lot number.
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    M2
    		2.24.50.2 to 0.4—10098689A11000000
    M2.5
    		2.75.00.4 to 0.6—10098689A1110000
    M3
    		3.26.00.4 to 0.6Material Certificate
    		10098689A1120000
    M4
    		4.38.00.4 to 0.6Material Certificate
    		10098689A1130000
    M5
    		5.39.00.9 to 1.1—10098689A1140000
    M6
    		6.411.01.4 to 1.8—10098689A1150000
    M8
    		8.415.01.4 to 1.8—10098689A1160000
    M10
    		10.518.01.4 to 1.8Material Certificate
    		10098689A11700000
    M12
    		13.020.01.8 to 2.2—10098689A11800000
    M14
    		15.024.02.3 to 2.7—2598689A1190000
    M16
    		17.028.02.3 to 2.7—2598689A12000000
    M20
    		21.034.02.7 to 3.3—1098689A1210000
     
    Highly Corrosion-Resistant 316 Stainless Steel
    M3
    		3.26.00.4 to 0.6—10098690A1100000
    M4
    		4.38.00.4 to 0.6—10098690A1110000
    M5
    		5.39.00.9 to 1.1—10098690A1120000
    M6
    		6.411.01.4 to 1.8—10098690A1130000
    M8
    		8.415.01.4 to 1.8Material Certificate
    		5098690A1140000
    M10
    		10.518.01.4 to 1.8—5098690A1150000
    M12
    		13.020.01.8 to 2.2—2598690A1160000
    M16
    		17.028.02.3 to 2.7—1098690A1170000
    M20
    		21.034.02.7 to 3.3—1098690A11800000
     
    Steel
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    Black Super-Corrosion-Resistant-Coated 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.
    Material Certificate—Washers include a report with a traceable lot number.
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    M2
    		2.24.50.2 to 0.4—10098688A11000000
    M2.5
    		2.75.00.4 to 0.6—10098688A1110000
    M3
    		3.26.00.4 to 0.6—10098688A1120000
    M3.5
    		3.77.00.4 to 0.6—10098688A1130000
    M4
    		4.38.00.4 to 0.6—10098688A1140000
    M5
    		5.39.00.9 to 1.1—10098688A1150000
    M6
    		6.411.01.4 to 1.8—10098688A1160000
    M8
    		8.415.01.4 to 1.8—10098688A1170000
    M10
    		10.518.01.4 to 1.8Material Certificate
    		10098688A1180000
    M12
    		13.020.01.8 to 2.2—10098688A11900000
    M14
    		15.024.02.3 to 2.7—5098688A12000000
    M16
    		17.028.02.3 to 2.7—2598688A1210000
    M18
    		19.030.02.3 to 2.7—2598688A1220000
    M20
    		21.034.02.7 to 3.3—1098688A1230000
    M24
    		25.039.03.7 to 4.3—598688A1240000
     
    Black Super-Corrosion-Resistant-Coated Steel
    M6
    		6.411.01.4 to 1.8—1093413A33500000
    M8
    		8.415.01.4 to 1.8—1093413A33600000
    M10
    		10.518.01.4 to 1.8—1093413A33700000
    M12
    		13.020.01.8 to 2.2—1093413A33800000
     
    BrassAbout Brass
    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.
    Material Certificate—Washers include a report with a traceable lot number.
    For Screw
    Size
    ID,
    mm
    OD,
    mm
    Thk., mm
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    Brass
    M1.6
    		1.73.50.2 to 0.4—10098691A11000000
    M2
    		2.24.50.2 to 0.4Material Certificate
    		10098691A1110000
    M2.5
    		2.75.00.4 to 0.6—10098691A1120000
    M3
    		3.26.00.4 to 0.6—10098691A1130000
    M4
    		4.38.00.4 to 0.6—10098691A1140000
    M5
    		5.39.00.9 to 1.1—10098691A1150000
    M6
    		6.411.01.4 to 1.8—5098691A1160000
    M8
    		8.415.01.4 to 1.8—2598691A1170000
    M10
    		10.518.01.4 to 1.8Material Certificate
    		2598691A11800000
    M12
    		13.020.01.8 to 2.2—1098691A1190000
    M14
    		15.024.02.3 to 2.8—1098691A12000000
    M16
    		16.028.02.3 to 2.7—1098691A12100000
    M20
    		21.034.02.7 to 3.3—198691A1220000
     
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