This system features 4-piston, S4 calipers mounted to 11", 2 piece slotted, drilled, zinc plated rotors. The S4 caliper has D.O.T compliant dust and weather seals. Billet aluminum hubs come assembled with premium bearings packed with Redline synthetic grease and billet dust caps. Rotors are pre-assembled with NAS high grade stainless hardware. All mounting brackets, stainless braided hoses and hardware are included and comes assembled on OE style or 2" drop spindles. The 11" SS4+ is designed just like Baer's larger systems, but in a smaller package for 15" wheels. All of Baer’s products feature material sourced from the USA. Products are also machined in house and the fit and finish are completed all in Phoenix, AZ.