This unique taper drill bit with drift key assists the pre-drilling of holes for the dry cores and saves the core skidding off the workpiece. As soon as the hole is started, this can be removed from the shank, giving a fast and friction-free cut. Comes with a drift key. Drift key is to assist in the removal of the A taper drill bit from the shank after the hole is started. A quick clout of the hammer, on the drift key, knocks the A taper drill bit out of the shank.