PowerSkin Spare Rechargeable Battery Case for Samsung Galaxy S4 - Retail Packaging - Black Only 5.7 mm thickness to your device Sleek and slim contemporary one-piece design for quick and easy installation Capacity 1600 mAh battery offers the power you need to make it through the day Polycarbonate material protects and fits to your phone's natural shape Polycarbonate material protects and fits to your phone's natural shape