Front disc brake conversion kit for 1964-74 GM A F X-Body models allows you to upgrade to 11″ rotors and 1969-77 GM midsize calipers on your stock 1964-74 disc brake spindles or our K6151 or 154893 disc brake spindles. Each kit is designed to be installed using stock style disc brake spindles (sold separately) and includes vented plain 11″ rotors and natural finish brake calipers. This kit is designed to be used with 15″ or larger disc brake compatible wheels. Not compatible with drum brake spindles.Each Kit Includes:Part # 154897 GM midsize single piston 2-3/4″ bore calipers with 7″ mountPart # GM5514 Vented plain 11″ rotors 5″ x 4.