Renthal Ultralight rear chain wheels are manufactured to extremely tight tolerances from a special material developed to withstand the rigors of supercross, motocross and enduro racing. The 7075 T6 aluminum alloy rear chain wheels are 66% lighter than steel, yet incredibly durable. Their advanced tooth profile, concentricity and accuracy of fit provide maximum power transfer and long-life. Renthal's combination of a very high strength base material and an exceptionally hardwearing surface result in significantly increased chain wheel life over other brands. Features Renthal Ultralight rear chainwheels are 66% lighter than steel Precision CNC manufactured to extremely tight tolerances High strength specially enhanced 7075 T6 aluminium alloy Computer aided Ultralight design gives the maximum reduction of unsprung weight at the rear wheel, to give maximum power transfer Self-cleaning mud grooves between every tooth on both sides prevent dirt build up Renthal Ultralight chainwheels are used by more factory motocross and supercross teams than any other chainwheel in the world