This lightweight, environmentally conscience with our aluminum portable solar powerbanks! Packed with high power, these banks have a capacity of upto 4000mAh with a micro USB charging cable included. Featuring a flashing charging indicator LED and USB port to allow charging to any device, this device is both smart and user friendly. With its slime design, this device only measures 3 3/4″ L x 7/8″ W x 7/8″ H with an imprint area of 2 7/16″ L x 1/2″ on the front back and 3 3/8″ L x 1/2″ W on the side, you can have your logo screen printed, full color print, pad-printed or laser engraved to your design.