This system features the 4-piston, S4 caliper mounted to a 12" x 1.100" 2 piece, slotted rotor and uses the popular DR1/HB100 pad type. The slot only rotors are mounted to 6061 billet aluminum hats using NAS high grade stainless hardware and come pre-assembled. All additional mounting hardware is also included. The SS4+ 2.0 Deep Stage system was designed to allow consumers to push the limits at the strip, yet still have a system that can be driven on the street. The SS4+ 2.0 Deep Stage system fits many 15in and larger wheels. NOTE: This system comes equipped with a high friction pad that is optimized for drag race applications. These pads often produce more dust and noise. Drag Race systems come standard in Clear and Fire Red caliper colors.