Material: Copper washer, which is made of high quality copper, the Copper Flat Washers is durable, rust-proof and has good electrical and thermal conductivity, and its melting point reaches 1083 ° C. Size Types:Different sizes flat washer: M5, M6, M8, M10, M12, M14, M16, M18, M20, M22. 15 types Flat Washers can meet your different needs. Practical: The copper drain gasket can distribute the load and avoid damage to the surface to be fixed, and isolate the steel screws from the surface; if the hole diameter is larger than the fixing nut diameter, a flat washer can be used. Widely Used: Gaskets Ring, can be used for oil pan plug, vehicle brake line, fuel oil, oil line, hydraulic accessories, also used for preload indicator, lock and reduce vibration Gasket Kit: Contains the most commonly used copper gaskets in 15 sizes (M5-M22), 150pcs flat ring copper washer packed in a compact, transparent and compartmentalized plastic case, which allows you to easily find the series and avoid loss