GPS Automotive - 9" power booster , 1-1/8 in Bore Cast Iron Master with chrome lid, bottom mount valve. Disc/drum (Chrome) New 9" chrome plated power brake booster, master cylinder & disc/drum proportioning valve combo This 9" power booster is hand polished before a chrome finish is applied for a top quality finish The top quality power brake booster is designed mount directly to your factory firewall Also included in this kits is a new 1-1/8" bore master cylinder and proportioning valve equipped to work with front disc rear drum applications