The Extreme+ system comes with the 1-piece Monoblock 6-piston, 6S caliper mounted to a 15", 2 piece slot, drill, zinc plated rotor. The 6S caliper is fully machined in Phoenix, AZ from a US sourced 2618 Aluminum forging, includes stainless steel pistons and abutments, D.O.T. compliant dust and weather seals and uses the popular D1247 pad type. Rotors are pre-assembled with NAS high grade stainless hardware. All mounting brackets and hardware are also included. The 15” Extreme+ fits most 19” or larger wheels.