This robust, ul certified power bank lives up to its name. With 4,000 mah, the commander unites power and portability in a modern matte metallic aluminum case. The t139 commander can recharge your electronic device through its single usb 1a output port on the go while attached to your phone with the included silicone smartphone strap. Its led digital battery status display will let you know how much power remains. Your brand will proudly command attention when decorated on both the power bank and the silicone strap!