The belts exceed USA RMA published ratings levels. They are designed to perform at the identical or higher level than all other major USA Manufacturer's belts of the same Type. The outside fabric wrap is treated with highly oil and heat resistant, engineered synthetic rubber compound, specifically compounded for excellent wear resistance, proven through thousands of hours of testing. Specially compounded for cool running, flexibility, crack resistance, and excellent bonding to the outer fabric and tensile cords.