Renthal Rear Sprocket YZ+F 99-.. Fantic XE/XX/F 21-.. 51t GPSI

Renthal Ultralight™ rear chainwheels are manufactured to extremely tight tolerances from 7075 T6 aluminium alloy which is 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 high strength base material and exceptionally hardwearing surface result in significantly increased chainwheel life over other brands.