ISSEC 2 Piece USBBatt AA Rechargeable Portable Energy Saving Battery Strong?Elastic?Retainer?(so?you?don't?lose?the?cap) Power?Source:?USB?5V?DC?or?Can?be?Charged?by?Conventional?Charger LED?light?on?showing?battery?when?charging,?light?off?when?finish?charge Case?material:?stainless?steel?cover Dimension?(AA):?50?(L)?x?15?mm?(Diameter)