Wentronic MP f/ ERI K850/W580(BST-38) 700mAh Li-Po. Battery technology: Lithium Polymer, Battery capacity: 700 mAh, Battery voltage: 3.6 V. Weight: 18 g, Width: 40 mm, Depth: 41 mm. Colour of product: Black, White. Dimensions (WxDxH): 40 x 41 x 5.5 mm