Juice Pack Plus Case and Rechargeable 2000mAh battery extender for iPhone 4 & 4S -Purple Ultra-impact-resistant, shock-proof band adds an extra layer of protection Rechargeable lithium polymer battery more than doubles your time to rock, talk, surf and send Pass-through USB charging and sync with iTunes Extended smart battery and full case protection Standby switch offers choice of battery or case and the integrated 4 LED light indicates your charge status.