EPDM rubber is a terpolymer of ethylene, propylene, and non-conjugated dienes, and commercial production began in 1963. Annual worldwide consumption is 800,000 tons. The main characteristic of EPDM is its excellent resistance to oxidation, ozone and erosion. Since EPDM belongs to the polyolefin (PO) family, it has excellent vulcanization characteristics. Of all rubbers, EPDM has the lowest specific gravity and can absorb large amounts of fillers and oils with little effect on properties, making it possible to make low-cost rubber compounds.