A 40V Max 4.0 Ah XGT Battery. This offers digital communication between the battery & the tool & battery & the charger. Thanks to the tool/battery communication the potential extraction rate of XGT Li-ion battery is higher than that of the LXT Li-ion battery. This battery is able to record more detailed information on battery usage history in comparison to existing batteries. There also a host of safety measures in place. There is a cooling system for maximum battery life, it has been developed for products used in continuous operations & finally there is greatly increased water & drop impact resistance. You can also keep on top of the battery level with the battery fuel gauge, a 4 LED gauge with a check button. Click to see the whole Makita XGT range.