Product details:

Corvette-stylemaster cylinder hasa 1-1/8 inch bore and is suited for disc/drum combinations. Features dual outlets so the plumbing can come out either side of the master cylinder. These master cylinders will work with manual or power brake systems. They come with a deep-well piston for manual brakes and an adapter to fill the deep well for use with a power booster.3/8 inch-24 IFF outlet ports. Plugs are included for the unused ports. Mount spacing is 3-3/8 inch on center. Brake System Selection.