Extra Power: Provides on-the-go charging for your mobile lifestyle Protection: One-piece protective case. Shock-proof, anti-dust, and sleek & slim. Battery Level: Indicator lights display charging status and battery level. Rechargeable: Built-in battery. All day, every day. On/Off Button: Puts power-on-demand in your hand. Simply hold down for 2 seconds to turn on or off. NFC Enabled: For your quick, information-sharing convenience.