Brembo F8X M2 / M3 / M4 GT-R Big Brake Kit - 345x28mm 2-Piece RearProduct Description: (R) 4 Piston Billet Monobloc Calipers 345x28mm (13. 6'') 2 Piece Discs Complete Axle Set Pre Assembled All Necessary Hardware Included INTENDED USE Street Track Race ___ ___ ___ ___ ___ CALIPER Body: Billet Monobloc Radial Mount Piston Configuration: 4 Piston Piston Design And Insert Type: Inner Pressure Seal Recessed Dust Boot Ventilated Stainless Steel Insert DISC Type: Cross Drilled, Type 1 Slotted, or Type 3 Slotted Material