1.O-ring :copper material 2.Seal gasket,metal gasket 3.passed ISO 9001,ISO Ts 16949 4.color, ... diameter,length according to requ 1.O-ring :copper material2.Seal gasket,metal gasket3.passed ISO 9001,ISO Ts 169494 ... .color,diameter,length according to requestO-RIing(seal gasket,metal gasket)It is made from copper,used for sealing .we ... .The material can be chosen by the customers. O-Ring