Product Name: Copper Washer Total Size: 12 x 18 x 1.5mm/0.5 inch x 0.7 inch x 0.06 inch(Inner Dia x OD x T) Material: Copper Color: Copper Tone Net Weight: 165g Essential for Automotive and Small Engine Repairs. Washers made from copper are often used within piping, electronics, household products, and bio applications as copper is malleable and ductile - a biostatic surface that is a good conductor of heat and, when very pure, a good conductor of electricity. Copper Provides a Tighter Seal and Greater Heat Endurance than Steel and Rubber Washers. These obviously have industrial uses, but we also sell them to weavers, artisans who make wall hangings, a lady who uses them to accent macrame hanging baskets etc. Package Contents: 100 x Copper Washers Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.