The Brembo Rear GT big brake kit mounts at the rear with four-piston cast calipers and 380x28 two-piece drilled rotors in a Silver finish. Two-piece rotors improve heat management and replacement flexibility while the four-piston calipers increase braking control. This specific configuration is listed for 2012–2017 M5 (F10) rear applications according to the product description.
Brembo 12-17 M5 (F10) Rear GT BBK 4 Piston Cast 380x28 2pc Rotor Drilled-Silver