GSM CYC-PWR5 Ener-Pak Portable Power Pack 5000mAh Battery Back Up with Dual USB Charger Can charge two devices at the same time Charges an iPhone up to 4x on a single charge Two USB ports, 2.1a and 1a outputs Intelligent charge protection/ 5000 mAh li-polymet Battery with no Memory Effect Lightweight, only 4 oz and portable/ battery capacity LED indicator