Impact drill series bosch gsb bosch professional power 850 watt gear variable speed tool holders 12 inch 20 unf keyless weight 26 kg idle speed max 3 000 rpm blow count max 51 000 countsmin torque max 36 nm drill diameter in concrete 18 mm drill diameter in steel 13 mm drill diameter in wood 40 mm special features rightleft rotation auto lock slip clutch power supply mains operation operating voltage 230 v included in delivery auxil