Reduce un-sprung weight. 1986-91 RX-7 rear brake bell. Part of our two piece rotor design that will fit the stock caliper application. Brake Bell or Hat Sold separately! Rear assembly is 2 lbs lighter than the stock single-piece rotor assembly. Rotors are directional vanned to cool more efficiently than stock. Two piece design is stronger and handles more punishment than stock design which tends to crack under severe conditions. Some minor machining is required to the hub to allow these items to fit. Comes with instructions and assembly bolts. Purchase rotor separately.