Global O-Ring & Seal 388 O-Ring Epdm, 18-15/16ID x 19-3/8OD, 70 Duro, Round, Black

Ethylene Propylene Rubber (EPDM) is a Copolymer of ethylene and propylene. Furthermore, it is a terpolymer of ethylene and propylene with a small amount of a third monomer (usually a diolefin) to permit vulcanization with sulfur. Generally, EPDM possesses an excellent resistance to ozone, sunlight and weathering, and has very good flexibility at low temperature, good chemical resistance (many dilute acids and alkalis as well as polar solvents) and good electrical insulation property.

• Cure system: Peroxide-cured
• Standard EPDMs are usually sulfur-cured. Sulfur-cured compounds offer better flexible properties but are more prone to hardening and have an inferior compression set with high temperature
• Peroxide-cured EPDMs have better heat resistance and a lower compression set. It complies with long-time usage, especially for hose systems in the construction industry, but is more expensive and more difficult for production than the sulfur-cured EPDMs

Temperature Range:

• Standard Low Temp: -55°C (-67°F)
• Standard High Temp: 125°C (257°F)