New 7" Dual Diaphragm zinc plated power brake booster , master cylinder & 4 wheel disc proportioning valve combo. This 7" dual power booster is hand polished before a yellow zinc finish is applied for a top quality finish. The F100 Power Brake Booster's black powder coated mount and pushrod assembly is a direct fit to your factory firewall for that fresh factory look. Also included in this kits is a new 1-1/8" bore master cylinder and proportioning valve equipped to work with 4 wheel disc brake applications.