MiPow Power Tube 4000. Battery technology: Lithium Polymer (LiPo), Battery capacity: 4000 mAh, Battery voltage: 5 V. Weight: 110 g, Width: 30.4 mm, Depth: 108.5 mm. Colour of product: Black. Operating temperature range (T-T): -10 - 45 °C. Device interface: USB