1970 GM Factory Disc Brake Hold Off Valve. Application: 1970 F-body Camaro / Firebird / Nova. 1970 B-body - Impala / Catalina 1970 A-body - Chevelle / GTO / 442 / GS This kit includes the valve, bracket, and mounting bolt. This mounts on the master cylinder stud for disc cars. 70 GM Disc Brake Hold Off Valve. This is the valve that is needed to make your car factory disc brakes. The valve is mounted off the stud of the master cylinder and holds off pressure so the rear drums will kick on a second before the front disc's.
