... 3/4 5/16 rubber seal ring 1)We have kinds of material : NBR,HNBR,EPDM,SILICONE,VITON,NR,FLS ... product are molded rubber parts products like O rings, rubber seals, rubber band, oil seal,water seal and rubber gaskets ect.Item nameO ... RINGSizeCustomized/standard and nonstandardBrand Nameo ringMaterialNBR,HNBR,EPDM,SILICONE ...