For 10 and 12 bolt GM rear ends - 1964-1977 GM mid size cars, 1964-1977 Chevy Nova and 1967-1981 Camaro and Firebird. Uses big 11" finned drums and high performance shoes to give a tremendous performance improvement over the original 9" drums. No need to change the master cylinder or proportioning valve and all components come pre-assembled on new backing plates. 14" Wheels may not allow adequate clearance.