The Wahl Lithium Ion is the worlds first grooming device with Lithium Ion technology. It is the most advanced rechargeable battery technology. Its lighter weight, has almost no charge loss in storage, is environmentally smart & has no memory issues. Best of all, it provides 3x the run time, 2x the power, a 1-minute quick charge & 1 hour full charge which standard Ni MH / Ni Cad trimmers cannot do. Features Include Worlds First Environmentally smart 3x the run time, 2x the power 1min quick charge for 5mins use Up to 150 minutes run time from 1 hour charge.