Upgrade your car to a 1 in. dual bore master cylinder with our quick install kit. This kit allows you to upgrade your factory single bowl manual brake car to dual bowl manual brakes in no time. In this kit you receive the brake line necessary to route from the new master cylinder to your factory distribution block. Additionally we include an adjustable combo. This adjustable valve allows you to fine tune the amount of pressure your rear brakes receive in order to prevent rear wheel lockup. For those cars that require a pressure switch to activate your tail lights, this combo block has one built in for an easy connection. A great kit with a factory look and easy installation! Designed for 4 wheel drum brake applications.