Abstract: A threading and/or tapping device has a housing including a tubular portion and a chamber portion that provides a shelf for a motor. A shaft rotatably connected to a slide within the tubular portion extends downwardly through the chamber portion with a tool holder on its exposed end. The slide is movable by the operator to advance and retract the shaft and a gear train within the chamber includes a drive gear on the motor shaft and a driven gear through the axis of which the tool holder shaft extends to rotate therewith and to slide relative thereto as the operator advances or retracts the shaft. The housing includes means for detachably attaching it with the work holder shaft either normal to or axially aligned with a support.