... .any size for silicon O ring 2.Non-toxic,Waterproof,Dustproof 3Under high wear and pressure ... 4.OME welcom silicon O ring Features:1) AS-568, PG standard and non-standard Silicone ... : silicone, fluoro silicone, viton(FKM), neoprene, HNBR, NBR+PVC, NBR, natural rubber, SBR, IR, IIR(butyl rubber), CR (neoprene), EPDM, SBR ...