The Combined Tap enables the user to produce the tapping drill hole and the through thread in one operation without any tool changing. The tool incorporates a twist drill before the thread-tapping part. This tool can produce through threads up to a maximuthreaded depth of 2 x D. The Combined Tap is suitable for universal use in materials of mediumechanical strength: non-alloyed and alloyed steel sorts up to 600 N/mm², malleable cast iron, nodulized graphite cast iron, copper, brass, aluminium, aluminium-magnesiuand zinc alloys, red bronze, electron metal, pressure-cast zinc. This tool should be used on machines possesing an RP switchover facility for drilling and tapping. The feed rate must be adapted to the particular operation required - drilling or tapping. Tapping chucks with pressure compensation may not be used.