The 2598-22 M12 FUEL? 2-tool Combo kit is the most capable and most compact 12 V hammer drill driver and impact driver Combo kit on the market. Included is the M12 FUEL? drill driver (2503-20), the most capable, lightest weight and most compact 12 V hammer drill in the market. At only 6.6 in. and 2.8 lbs of weight it is the best hammer drill to use in compact spaces. It delivers the power to do a wide variety of applications at 1700 RPM?s and 350 in. lbs. Of torque. Also included, the M12 FUEL? 1/4 in. hex impact (2553-20), the fastest driving speed, most compact with 4- mode drive control impact driver in the market. At 3,300 RPM the impact drives screws over 20% faster than competitors. At 5.1 in. in length it allows for unmatched access in tight spaces. The 4-mode drive control provides greater control over output speed and power for greater versatility by delivering 0-1, 300 RPM in mode 1, 0-2, 400 RPM in mode 2 and 0-3, 300 RPM in mode 3. Mode 4 is self-tapping screw mode which is designed to reduce walking when starting self-tapping screws as well as reduce overdriving, breaking and stripping out screws.