The Dual Deep Stage Rear Brake kit features four, 4-piston, S4 calipers mounted to a 11" 2 piece slot, drill, zinc plated rotor for optimin clamping force. The S4 caliper has D.O.T compliant dust and weather seals and uses the popular DR1 or HB100 pad type. Rotors are pre-assembled with NAS high grade stainless hardware. Mounting hardware is also included. The SS4+ Dual 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.