64-66 Ford Mustang Wilwood Polished Master Cylinder and Black Powder Coated 7" Brake Booster with Brackets. Kit is designed for use with automatic transmissions. This master cylinder features polished finish with black anodized machined aluminum top. Master cylinder has a 1" bore and includes ports on both sides to work with all applications. Master cylinder outlets are 1/2-20 UNF and come with adapter fitting for 3/8-24 and 9/16-20. Master cylinder works with both disk/drum or disk/disk applications just change proportioning valve to match your set up.