GOESTIME 2000mAh Backup Power Cover Case For iPhone 6/6S External Battery Charger Bumper Case Power Bank (golden) 1)Innovative 3 in 1 functions including power bank, metal bumper, back cover case. 2)4000mAh battery capacity as a great backup power pack. 3)Comapact design with rock solid construction. 4)Fast recharging speed for possible emergance use 5)Portable, convenient, easy to use, high capacity