Wilwood’s 15/16" bore Tandem Aluminum Master Cylinder is designed primarily for manual applications and includes a pushrod. They’re designed for mount flanges from 3.22” to 3.40”, common measurements for most domestic cars and trucks from the mid 1960s to present, and offer fluid outlet ports on both sides of the bore. The stroke is set at 1.10” with a volume ratio of 2:1 between the primary and secondary chambers. Machined from high-pressure die castings, each master cylinder weighs only 3lbs, a 75% weight savings over most cast iron OE type master cylinders. 1/2-20 UNF ports.