GXL18V-251B25 Bosch 18V 2-Tool Combo Kit w/ Compact Tough™ Hammer Drill (GSB18V-535C), Socket Ready Impact Driver (GDX18V-1800C) w/ (2) 4.0 Ah CORE Compact Batteries The GXL18V-251B25 Bosch 18V 2-Tool Combo Kit with two CORE18V batteries combines drilling and driving versatility with next-gen Li-ion 21700 cell technology. The GXL18V-251B25 Bosch 18V 2-Tool Combo Kit features the GDX18V-1800C Bosch Freak: half driver, half wrench, all impact. The impact driver has a two-in-one bit/socket drive that offers a 1/4 In. quick-change hex shank holder for bits, and a 1/2 In. square drive for sockets. It produces up to 1,800 In.-Lbs. of torque. The GSB18V-535C Bosch Compact Tough 1/2 In. Hammer Drill/Driver has KickBack Control technology, up to 535 In.-Lbs. of torque, 0-28,500 beats per minute (bpm) and a precision clutch in a tool weighing only 2.7 Lbs. (tool only, not including battery). Both tools feature Bluetooth® connectivity to an optional Connected Tool Module and EC Brushless motors. GXL18V-251B25 Bosch 18V 2-Tool Combo Kit includes two next-gen CORE18V 4.0 Ah compact batteries. Each keeps the power and runtime, while losing the weight, with 21700 cell technology. The CORE18V matches the power of the original two-layer 4.0 Ah battery with half the number of cells. It features the CoolPack 2.0 heat-management system.