... quality motorcycle roller chain,1)material:40mn2)color : nature,black,blue,yellow3)advanced heat treatment process, mesh belt conveyor furnace use,chain dry machine4 ... )standard:ISO/ DIN /ANSI5)pre stretch and anti fatigue to make chain life longer6 ... 420,420H,428,428H,520,520H,6303)short pitch conveyor roller chain attachments:A-1,A-2.K-1,K-2,K ...