The dual-voltage FLEXVOLT 20V/60V MAX* 9.0 Ah battery automatically changes voltage when you change tools, providing up to 6X runtime** (** With DCB609 FLEXVOLT battery when used with DEWALT 20V MAX* tools compared to DCB201 1.5 Ah battery pack.) in 20V MAX* tools and the power of corded in 60V MAX* and 120V MAX* tools.