Product description Material: copper Quantity: 200 pcs. Color: Golden Package includes: 1 x storage box 30 x M5 * 9 * 1 30 x M6 * 10 * 1 20 x M6 * 12 * 1 20 x M8 * 12 * 1 20 x M8 * 14 * 1 20 x M10 * 14 * 1 20 x M12 * 16 * 1 20 x M12 * 18 * 1.5 20 x M14 * 18 * 1 1. 【Excellent material】 Our washers are made of high-quality copper material, which has good electrical conductivity, thermal conductivity, melting point of 1083, and is durable for daily use and can be used repeatedly. 2. 【Easy to use】 The sealing ring sets are very easy to install, the surface of the flat copper washer is smooth, and it can reduce friction between fasteners, prevent leakage, insulate, prevent loosening or spreading pressure. 3. 【Easy storage】 These sealing rings are equipped with a storage box, which makes the sump plug washers safer and more convenient to store, easy to carry and easy to classify. This design improves work efficiency. 4. 【Wide range of applications】 The assortment of o-rings is ideal for water, sump plugs, fuel and hydraulic fittings. The copper rings are perfect for electrical connections for household and commercial appliances as well as automotive and marine applications. 5. 【What you get】 The copper sealing ring assortment includes 30 pcs. M5 * 9 * 1, 30 pcs. M6 * 10 * 1, 20 pcs. M6 * 12 * 1, 20 pcs. M8 * 12 * 1, 20 pcs. M8 * 14 * 1, 20 pcs. M10 * 14 * 1, 20 pcs. M12 * 16 * 1, 20 pcs. M12 * 18 * 1.5, 20 pcs. M14 * 18 * 1, perfect for electrical connections in household, commercial appliances, cars and ships.