Girodisc Ferrari F430 Challenge Front RotorsThe Girodisc system is a direct replacement for the OE disc however a different brake pad with an annulus (pad swept area) of 66mm or less must be used. This is done to keep the rotor weight at a reasonable level. If we manufactured a rotor with the same annulus as the OEM CCM rotors they would be far too heavy. The necessary pad shape is very common and also found on the Nissan GT R, Cadillac CTS V and most AMG Mercedes equipped with 6 piston