Whether you're building a brake system from scratch, or upgrading from an older outdated worn system. The Aeroflow Performance brand new slimline brake master cylinders install easily, as most mount in the stock location. They feature dual reservoirs and shallow pockets which accommodate front disc/rear drum brakes or 4-wheel disc systems. We offer a variety of designs to provide compatibility with manual brakes as well as power-assisted applications. Each master cylinder has a GM universal mount spacing (3-3/8") to suit a variety of universal or bolt-on applications. Available in a chrome and black finish and in a 1-1/8" bore size and constructed from cast iron.