This simple to install conversion kit upgrades your stopping power by up to 20%. The existing 160mm disc will convert into a 180mm full circle type brake disc with this kit. As bicycle discs use a 6 bolt standard center hub internationally, you have a choice of either upgrading to a contoured disc or full circle. An international bolt spaced standard relocation bracket is included to aid in repositioning stock calipers in alignment with a new oversize disc.