The Orepd045X50 O-Ring From Sterling Seal Is Rated For Steam (400 Degrees Sterling Seal, EPDM O Rings have great acceptance in the sealing world because of its excellent resistance to heat, water and steam, alkali, mild acidic and oxygenated solvents, ozone, and sunlight (UV). These compounds also withstand the effect of brake fluids and Skydrol" and other phosphate ester-based hydraulic fluids. OREPD045x50 EPDM rubber (ethylene propylene diene monomer rubber) is an elastomer which is characterized by wide range of applications and good chemical resistance EDPM is also resistant to ketones, hot and cold water, and steam EDPM has good heat and compression resistance and its standards is good for Auto Brake Fluids EDPM's service temperature -65 F to 302 F (-54 C to 150 C) EDPM?s limitations are oils, gasoline, kerosene, aromatic and aliphatic hydrocarbon, halogenated solvents, concentrated acids, non-polar solvents, petroleum oils and aromatic fuels