This system features the 4-piston, S4 caliper mounted to a 11" 2 piece slot, drill, zinc plated rotor. The S4 caliper has D.O.T compliant dust and weather seals and uses the popular DR1 or HB100 pad type. With 1.75” pistons, the S4 Deep Stage caliper will offer additional clamping force over the standard S4 caliper. While this usually desired in a drag race application, it may not be ideal for street use. Rotors are pre-assembled with NAS high grade stainless hardware. Mounting brackets and hardware are also included. The SS4+ Deep Stage system is the first drag race system designed specifically for heavy, fast cars that might also see street use. The 11" SS4+ Deep Stage system fits most 15” and larger wheels. *** NOTE: This system was designed for racing only. If used on the street (due to brake bias change) be sure to spend some time to make sure adjusted correctly. ***