A self contained set for accurate facing of a bottom bracket shellsimple to use tool which ensures the seating faces of a bottom bracket shell are parallel which is essential for the smooth running and long life of bottom brackets especially shimano hollowtech iicomes with threaded inserts to ensure the tool is in the perfect position for accurate facinga powerful spring keeps the cutter at the ideal pressure for a perfect jobhigh quality cutting head is replaceableuse with plenty of cutting oil