Let The Cal Powerbank Rev Up Your Promotional And Advertising Efforts. This 13/16" X 3 3/4" Rectangular Metal Powerbank Is Small Enough To Fit In The Palm Of Your Hand, But Packs 2200mah In Recharging Power. Features An On / Off Button. Just Plug In The Included Cable, Which Has Both Standard And Micro-usb Ports, Into The Bank And Your Favorite Device. Compatible With All Smartphones.