240sx Upgraded Master Cylinder (1" inch)This is a rebuilt 1 inch master cylinder. Many people who have after market brake kits installed on their car use this master cylinder to compensate for the added piston area that has to be accounted for. This upgrade will make your brake pedal have less play when adjusted correctly. It is a 12. 5% percent increase in brake fluid. Stock 240sx use a 7 8 master cylinder. If you are planning on getting upgraded brakes this is a highly recommended part