... our factory, it is made from Nitrile(NBR), HNBR ,EPDM, Silicone, Fluorine(FKM,FPM), Neoprene(CR),Styrene(SBR) ,CR,ACM,PU ... : O ring is widely used in different industries: Auto, Machinery, Electronic, Water facility, Valve accessories, Air-conditioner, Sanitary ware and so ...