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    7 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.
    Material Certificate—Washers include a report with a traceable lot number.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    For Screw
    Size
    ID
    OD
    Thk.
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    Certificate Type
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    18-8 Stainless Steel
    No. 10
    		0.195"0.354"0.030" to 0.034"NAS620C10LMaterial Certificate
    		25090945A740000000
    No. 10
    		0.195"0.354"0.060" to 0.066"NAS620C10Material Certificate
    		10090945A74100000
     
    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
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    Low-Friction Cadmium-Plated Steel
    No. 10
    		0.195"0.354"0.031" to 0.033"NAS620-10L1005360N12400000
    No. 10
    		0.195"0.354"0.062" to 0.064"NAS620-101005360N1250000
     

    Countersunk Tooth Lock Washers

    These washers grip flat- and oval-head countersunk screws, so you get a secure hold without overtightening. They resist loosening in applications with constant motion, such as conveyors. Tooth lock washers typically can't be reused because the teeth often get bent when tightened.
    External Tooth
    Image of Product. Front orientation. Lock Washers. Tooth Washer, Countersunk Washer, External Tooth.
    Teeth on the outside edge bite into both the screw head and the mating surface to lock the assembly in place. 
    Wear-Resistant 400 Series Stainless Steel—These grip hard material better than other types of stainless steel. They are not as corrosion resistant as 18-8 and 316 stainless steel, so they are best for environments that experience occasional moisture.
    Zinc-Plated Steel—A common choice for areas with 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.
    For Screw
    Size
    ID
    OD
    Thk.
    Countersink
    Angle
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Wear-Resistant 400 Series Stainless Steel
    No. 10
    		0.195"0.354"0.020" to 0.025"82°
    		ASME B18.21.12590900A01200000
     
    Zinc-Plated Steel
    No. 10
    		0.195"0.354"0.020" to 0.025"82°
    		ASME B18.21.15090069A11500000
     
    Black-Oxide Steel
    No. 10
    		0.195"0.354"0.020" to 0.025"82°
    		ASME B18.21.12590069A21400000
     
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