... -ring Made by SILICON, NBR, SBR, NR, CR, EPDM and FKM We are professional rubber products supplier certified to ISO9001:2008 ... Made Rubber seal, valverubber gasket1)Available material: silicone, NBR, fluorosilicone, viton (FKM, FPM), CR, NBR, HNBR, PVC, PU, NR,SBR, IIR, AU ...