This kit employs the same 6-piston front/4-piston rear Brembo calipers as our E92 BBK and adds 380mm GiroDisc rotors in front and 370mm GiroDisc rotors in the rear.  Paired with Hawk HPS60 pads, stainless brake lines, and of course, custom Partee Racing proprietary brake brackets made from 7075 T6 aluminum, this BBK is hard to beat, especially at this price.  Unless one is going all out and opting for the Partee Racing AP Racing kit, this is the BBK to have for the E39 M5. NB:  THIS KIT DOES NOT FIT UNDER STYLE 65 WHEELS.  It does fit nicely under forged Apex and similar aftermarket wheels.