Uchikome Drills has a protruding part like a tsuba at the base of the ears (two tsuba and one tsuba). It is used to drill holes for the injection of large nails into the member. After hitting the hole until the depth is appropriate, hit the tsuba from below and pull it out. It is the same as the tsubachisel, but the cross section of the tip is inserted into the Drills and the tsubachisel is square.