... ,m6,m8,m10,m12,1/4",1/8" shape:flat or ring offer OEM Wide range of applicable working conditions ... pressure resistance, applicable to super low temperature. The copper washer is used in machinery fields. It has a good thermal ... content is more than 99.0%, and we dealing our washer with annealing and acid cleaning processes, the hardness is ... the picture show), or 100pcs/box. high quality copper washer