Detachable lithium-ion battery. Removable with one touch. Can be charged while inside the main unit. I purchased this used as a spare battery, but I rarely used it. I have confirmed approximately 12 minutes of continuous use on a full charge, so I don't think the battery has deteriorated much. There are some minor scratches from installation. No box or instruction manual. Battery only. *Shipping method may change between Rakuraku and Yu-Yu. Compatible Products EVOPOWER W20 (WV250J) W25 (WV270J) W30 (WV251J, WV251JBZ, WV251JLS, WV251JSV) W30P (WV260J) W35 (WV280J) W35P (WV285J) Specifications ◎Size (Height x Width x Depth) 49 x 145 x 43mm ◎Weight 203g ◎Color Black