The dual-voltage 20/60 V MAX FLEXVOLT® 9 Ah battery automatically changes voltage when you change tools, providing up to 6x runtime in 20 V MAX tools and the power of corded in 60 V MAX and 120 V MAX tools. Take on tough jobs with this battery because patented technology and large format cells mean it runs cooler than the leading competitor 9 Ah battery pack under a constant discharge. This is the battery for FLEXVOLT® power and long runtime. Dual-voltage for ultimate flexibility. 6x run-time when used in a 20 V Max tools. Compatible with all 20 V Max chargers. Silicone encapsulated module helps keep dust and debris out. LED charge status display on battery. 180 W-hr of energy in each battery pack, get 360 W-hr when using (2) Flexvolt® 9 Ah batteries in 120 V Max tools. Runs cooler than leading competitor 9 Ah battery for better efficiency. Operates in outside temperatures down to 0 deg F.