DBA 15-20 Mini Cooper JCW Hatchback Front 5000 Series Replacement RingSharing all the benefits of the 4000 Series, DBA's 5000 Series rotors are a composite 2 piece direct replacement brake rotor. DBA uses only the highest quality materials to ensure optimal performance under the most strenuous circumstances, combining high carbon cast iron rings with aerospace grade aluminum hats (T6061 T6), held together with National Aerospace Standards (NAS) bolts and crimp nuts. The 5000 Series share all of the performance