Product Name: Copper Washers Total Size: 12 x 18 x 1.5 mm/0.5 inch x 0.7 inch x 0.06 inch(Inner Diameter x OD x T) Material: Copper Color: Copper Tone Net Weight: 330g Essential for automotive and small engine repairs. Copper washers are often used in piping, electronics, household products, and bio-based applications because copper is malleable and ductile - a bio-based material that is a conductor of heat and, when pure, a conductor of electricity. Copper provides a tighter seal and greater heat resistance than steel and rubber washers. These are obviously industrial uses, but we also sell them to weavers, artisans who make wall hangings, a lady using them to accent macrame hanging baskets, etc. Package Contents: 200 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 a little different from the real thing. The measurement allowed error is +/- 1-3 cm.