Material: Copper. High conductivity, corrosion resistant. Good electrical conductivity and thermal conductivity. It contains 300pcs/12 sizes of the most commonly used copper washers. Ideal for sump plugs, water, fuel and hydraulic fittings. Come with a plastic storage box for storage. Durable copper material that lasts a long time. Perfect for electrical connections of household and commercial appliances, automobiles and marine, in which the power source has a threaded/bolt connection . The package includes: 300 x Copper Washer, 1 x Plastic Box. Motor Copper Washers - Flat Washers Assortment - Assorted Flat Washers - Sealing Washers Kit - Plain Washers for Hardware Accessories Product Features : Top quality copper. Good electrical conductivity and thermal conductivity. Excellent for sump plugs, water, fuel and hydraulic fittings. A drain plug washer to fit all types of engines: car, marine, generators, machinery and factories. Product Features : *Product Name : Matching copper washers. *Material : Copper. *Quantity : 300 pieces. Color: Gold Dimensions: M5 x 9 x 1 35 pieces M6 x 10 x 1 30 M6 x 12 x 1 30 M8 x 13 x 1 30 M10 x 14 x 1 30 M8 x 14 x 1 25 pieces M12 .5 15 pieces M20 x 26 x 1.5 15 pieces ladaceae