portable battery for iphone 3G/3GS ,Original R&D and Manufacturer ... 3G /3Gs/4G Product Description: This is a universal external battery pack , compatible with Iphone 3G 3GS/4G.Configuration: # ... This product made up of lithium battery,1pcs PCB board, and housing # Color: Black,white # ... #Cycle life:>=500 # sleep current:<=0.05Ma External Battery/Power Pack for iphone1900mA