This is a reproduction Cast Iron Lower Alternator Bracket for Big Block 1965 thru 1968 Chevelle, Chevelle SS. Also for 1966 thru 1968 El Camino, 1968 Chevy II Nova, and 1966 thru 1968 Impala, Caprice, BelAir, and Biscaiyne, and 1968 thru 1972 Chevy Pickup Trucks. This is the one that has the hole in the extension arm centered, and is not the cheap version of this bracket