EPDM is ethylene propylene diene monomer, a type of synthetic, high-density rubber. Standard commercial grade EPDM rubber is sulfur cured and has resistance to oxygen, weathering and ozone.  Works best if the application is flat and not under stress.

Common characteristics of EPDM are good aging resistance and broader temperature range and lower electrical conductivity.  Peroxide cured EPDM is normally used for a broader range of temperatures and chemical resistance.

White EPDM is available for Food or other sanitary applications.  For mechanical fastening, high compression load on flanges and where excellent dimensional stability is required, nylon inserted EPDM is the typical material used.