6.DC-DC quick charging boosted circuit built-in,use two pieces battery can boosted to 5V,transfer efficiency can reach to more than 98%,Use new 5#AA battery can charge the android phone(2500MAH battery) to 40% within 30 minutes.
7.Built in protection circuit,When the AA battery used or the device charged full,it will stop charge by itself.
8.Only need two pieces 5#AA battery that very easy to buy anywhere then can charge your android phone/MP3/MP4/PSP/GPS anytime.