... .Material CR 2.Good tensility,wearing 3.ROHS,ISO9001,14001 4.Type:X ring,U ring,V ring,O ring,etc CR Rubber ... o ring 1. Main materialNeoprene(CR),also can use Natural rubber, SBR, NBR ... , IIR, PU, EPDM, Silicone, FKM, FVMQ, HNBR, ECO, ACM, etc.2. CertificationISO ...