Rubber Roll, EPDM Cloth Inserted 1 PLY, Rubber Width 36 in, Rubber Length 40 ft, Rubber Thickness 1/16 in, Black, 60A, Plain backingâ¢Good aging resistanceâ¢5oz Nylon Reinforcementâ¢Lower electrical conductivityâ¢Resistance to oxygen, weathering and ozoneâ¢EPDM works best in flat applications not under stress.