Girodisc BMW G8X M2, M3, M4 370mm Rear RotorsThese GiroDisc 2 piece rotors are a direct replacement for the rear rotors on the G80 M3, G82 83 M4, and G87 M2 without carbon ceramic brakes. Our 2 piece, fully floating assemblies help shed unsprung weight and rotating mass from the front axle of the vehicle. The rotor rings are machined from a proprietary casting made of high carbon iron formulated to GiroDiscs specifications. This superior metallurgy results in a rotor that holds up better, and