WILWOOD ALUMINUM MASTER CYLINDERS These aluminum master cylinders from Wilwood have many of the features you've been asking for. All new die cast housings allow a better finish in the bore, less porosity and more accurate castings. Includes an internal return spring and baffles to decrease sloshing. They also hold 8.2 ounces of brake fluid, which is 26% more than most brands. That means cooler brake fluid for less brake fade. Available in three bore sizes: 7/8" and 1". All have a 1/8" NPT single outlet. Overall body height is 4-7/16" and overall body length is 3-9/16".