WORX 20-volt Max Lithium 1.5Ah battery is suitable for series: WG151, WG151.5, WG155, WG155.5, WG251, WG251.5, WG255, WG540, WG540.5, WG890, WG891. The Lithium Technology charges quickly and powers your cordless WORX tool through the entire job, without waning or draining. Max lithium batteries are lighter, more efficient, and charge with no memory effect.