The FLEXVOLT 20V/60V MAX* 15.0 Ah battery provides the highest capacity of any battery on the DEWALT cordless system.It changes voltage when going from 20V MAX* to 60V MAX* tools and is compatible with a variety of 20V MAX* tools and chargers.In 20V MAX* tools it will provide extended run time. In 60V MAX* it will deliver cordless 60V MAX* power.