18650 lithium batteries, Charge and discharge over 700 times which is 2 times more than ordinary battery.Intelligent current control: when phone power is low, the current will be adjusted to large.Super compatible with the market 99.9 percent of smartphones, tablets, i-Phone, MP3 / 4, PSP, GPS and other digital devices Multiple protection to ensure safe working Portable power box, compatible with a variety of electronic devices, smart phones, tablets, bluetooth headset for iPhone and iPad.Built-in rechargeable battery, simple design.High efficiency of power conversion with Electricity-saving function , Portable, practical and long cycle life.Safe and reliable, perfect for using on traveling and outdoor activities.Batteries Type: 18650 lithium batteries Capacity batteries: 5000MAH Operating temperature: 5 C-45 C Intelligent LED power indicator: Yes Material: ABS heat-resistant fire prevention materials Switch mode: Auto-sensing Input: DC5V-1A Input Current: 1A Output: DC5V / 1A Conversion efficiency: 91%