Abstract: A tool set includes a T-shaped handle, a connector unit having a truncately conical cavity, a screw tap and a screwdriver piece. A socket having a truncately conical end is secured to the handle and has a hexagonal cavity formed in the end surface thereof, and an annular groove formed in the inner surface of the socket. A retaining ring is received within the groove. Both the connector unit and the screwdriver piece have a hexagonal cross-sectioned plug which has circumferentially concaved portions. By matching the truncately conical cavity of the connector unit with the truncately conical end of the socket, and by engaging the hexagonal cavity of the handle with the plug in such a manner that the retaining ring snaps into the concaved portions of the plug, the assembly of the handle, the connector unit and the tap can form a T-handle-type tapping tool, or the assembly of the handle and the screwdriver piece can form a T-handle-type screwdriver.