... s demond 3.Many standards available Product: glow in the dark o ring O ring is a kind ... through the molding way to make it in the ring ship. It is generally used to seal the fluid liquid or gas, ... often works as a part of the ... both in static seal and dynamic seal, main material contains: NR, CR, NBR, SBR, VITON, SILICON, HNBR, PU etc ...