Featuresusb interface design convenient to charge by power adapter laptop or desktopcombination of qi charging pad and 4000 mah power banksupport wireless charging for one device and usb charging for another device simultaneouslytouching key to turn on the power bank convenient to operatebuilt in 4000 mah battery charge for tablet pc mp3 psp digital camera and other mobile devicesconvenient to charge at home or on your office desk and portable for travelbuilt in overcharging prote