Also included with this pedal is a high quality 7" single diaphragm zinc booster and master cylinder combo. The booster has a 3 3/8" bolt pattern ~ square. This includes a bolt-on brake pedal assembly designed for 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 & 1948 Chevy cars.
