Rear Brake Reservoir Extender CNC machined from 6061-T6 aluminum, Increase the volume of rear brake reservoir to provide additional cooling and performance, More aluminum surface area contacting caliper to transfer far more heat away, Reduced brake fluid temperature and keeps braking performance stable, Allows your rear brake system to perform better in hot and extended riding conditions, Larger fin surface area dissipates heat, It allows the use of the stock bleeder bolt