... :ISO 9001:2008/SGS test report/ROHS report Stainless steel ball Name: Stainless steel ballsMaterial: AISI304,316,420C,440CSize: 0. ... hardness (60 HRC). It has good resistance to the atmosphere, fresh water and mild acids. It has best resistance in the ... industries (valves, pumps and bearings).OUR MAIN PRODUCTS:Stainless steel ball:AISI302,304,316,420,4440CBearing steel balls:AISIE52100Carbon steel balls ...