Brembo E39 M5 GT Big Brake Kit - 345x28mm 2-Piece RearProduct Description: (R) 4 Piston Calipers 345x28mm (13. 6") 2 Piece Complete Axle Set Pre Assembled All Necessary Hardware Included INTENDED USE Street Track Race ___ ___ ___ ___ ___ CALIPER Body: Cast 2 Piece Radial Mount Piston Configuration: 4 Piston Piston Design And Insert Type: Inner Pressure Seal OEM Approved Dust Boot DISC Type: Cross Drilled, Type I Slotted, or Type 3 Slotted Material Finish: Advanced High Carbon Alloy Corrosion Resistant