This system features the 6-piston, 6P caliper mounted to a 13", 2 piece slot, drill, zinc plated rotor. The 6P caliper has D.O.T compliant dust and weather seals and uses the popular D0731 pad type. Rotors are pre-assembled with NAS high grade stainless hardware. Billet aluminum hubs come assembled with premium bearings packed with Redline synthetic grease, billet dust caps and come pre-assembled on 2" drop spindles. All mounting brackets, stainless braided hoses and hardware are also included. The 13" Pro+ is designed to fit most 17” or larger wheels.