Master Cylinder: Disc/Disc Alloy Chrome 1 1/8" bore - 1/2" & 9/16 portsUltra Light Weight GM Universal Corvette Style Aluminum Chrome 1 1 8 inch Bore; 9 16" & 1 2" Ports on left Side; NOTE THE PORT SIZES.. Larger 9 16 port is at the rear on both sides. Master Cylinder has a piston adaptor that will allow for power booster or manual no booster applications. Looking for a Bling Master for Disc Disc early rear disc applications this may be a choice?? This is ideal for most disc x 4 conversions requiring ample fluid capacity