Our company produces all kinds of copper washers ,widely used,good in quality and competive in price. ... if you Standard: GB,DIN,ISO,JIS,BS,ANSI Material : copper yellow metal Types : plain washer O.D:3MM-2000MMDescription1)RTJ ... ,347,316,304 soft iron and the like.Besides, our company has been approved of API certificate and ISO9001:2000, therefore ...