Nitrile 70 rubber (NBR) is the general term for Acrylonitrile Butadiene Copolymer. Nitrile is the most widely used and economical elastomer. Nitrile combines excellent resistance to petroleum-based oils and fuels, silicone greases, hydraulic fluids, water and alcohols, with a good balance of such desirable working properties as low compression set, high tensile strength, and high abrasion resistance. Use of Carboxylated Nitrile can have superior abrasion resistance, while still having improved oil resistance.