Makita is the innovation leader in Brushless Motor technology, and the XT252MB combo kit gives you two BL Brushless Motor solutions that deliver longer run time, increased power and speed, and longer tool life -- as well as the industry-leading 18V Hammer Driver-Drill with a full 1,090 in. lbs. Of torque, the most in the category. The combo kit includes a BL Brushless Motor impact driver and Hammer Driver-Drill with category-leading torque, so it's everything you'll need for drilling, driving and fastening applications. The 18V LXT 4.0 Ah battery provides 35% more run time per charge than the 3.0 Ah battery (BL1830), yet it charges in only 40 minutes ï¾– the fastest charge-time in the category ï¾– for less downtime and increased productivity. For increased convenience, the batteries include an on-board L.E.D. charge level indicator. Itï¾'s part of Makita's expanding 18V Lithium-Ion series, the worldï¾'s largest cordless tool line-up powered by an 18V Lithium-Ion slide-style battery. Makita 18V Lithium-Ion batteries have the fastest charge times in their categories, so they spend more time working and less time sitting on the charger. For improved tool performance and extended battery life, Makita created Star Protection Computer Controls. STAR Protection is communication technology that allows the star Protection-equipped tool and battery to exchange data in real time and monitor conditions during use to protect against overloading, over-discharging and overheating. For increased versatility, the tool can also be powered by Makita 18V LXT and compact Lithium-Ion batteries with the star symbol on the battery indicating STAR Protection inside.