Wentronic MP f/ ERI R600 (BST-20) 650mAh Li-Ion. Battery technology: Lithium-Ion (Li-Ion), Battery capacity: 650 mAh, Battery voltage: 3.7 V. Weight: 26 g. Colour of product: Grey. Dimensions (WxDxH): 53.5 x 32.5 x 6 mm