Sterling Seal Inc style #7237 Red rubber is a Copolymer of styrene and butadiene with generally good physical properties making it an economical gasket Red rubber gaskets are often called SBR for short This synthetic material was developed as an alternative to natural rubbers Sterling Seal #7237 Red rubber SBR conforms easily to uneven flange surfaces, has good abrasion resistance, excellent impact strength, very good resilience and a high tensile strength Red rubber (SBR) is a very popular flange gasket material for hot or cold water SBR Red rubber is not suited for use with oils, fuels, solvents or hydraulic fluids Red rubber is the most cost effective rubber gasket option available for applications which require a sturdy industrial elastomer Sterling Seal Inc of NJ style 7237 have proven their long-term reliability over the course of many years