Check the listing for details. Chrome Disc Drum Proportioning Valve & Bracket GM 350 Master Cylinder Booster. Condition: New. Listed at 56.68 USD. Chrome Disc Drum Proportioning Valve & Bracket GM 350 Master Cylinder BoosterDescription:Brand new Chrome Aluminum Proportioning Valve and Side Bracket Mounting Kit with 1/2" Front and 9/16" Rear Brake LinesThis combination proportioning valve is for Disc/Drum applications.This valve performs all the necessary functions when using disc brakes in the front and drum brakes in the rear including the following Package:Chrome disc/drum proportioning valve and Side Bracket Mounting Kit(which allows you to mount this to the Left (Driver's Side) of any aftermarket or Stock Booster including 7" 8" 9" 10" and 11" sizes.)two hard lines that connect the master cylinder (with 1/2" & 9/16" ports) to the proportioning valve.As shown in our picturesTHIS KIT IS FOR DISC/DRUM APPLICATIONS ONLY! Professional Installation is Highly Recommended (No Instruction Included)