EnerPlex SFI-2000-GR Surfr iPhone 5/5s Case, Green Ultra Slim case with integrated 2000 mAh battery which provides 100% more battery life Integrated solar panel provides emergency energy. 30 minutes of sun produces a 5 minute phone call Slimmest and lightest battery case with integrated solar that provides robust protection for your device Charge and sync via Micro-USB with smart charge feature witch charges your phone before the case LED lights indicate battery life of case and when phone is charging via solar