Norton Rear Vernier Isolastic KitJust the thing for when your rear mount is getting sloppy! If you've gotten this far you know what these are all about. No frame mods necessary, just remove the old tired isolastic and install the new pieces. Adjustment is a matter of turning the collar instead of removing and installing new shims. Abutment pieces are stainless steel and will outlast the bike without siezing up.