Universal 8 inch Dual Diaphragm Brake Booster A dual 8 inch brake booster is a great choice for larger vehicles with space limitations. With it’s 3-3/8 inch square pattern on the rear and the GM pattern on the front, it is a great choice for builidng a system from scratch or replacing a defective booster. The booster requires a minimum of 18 inches of vacuum to operate properly.
