Back up Motorola ROKR E8 battery is a much needed necessity and you do not want to be without power for your Motorola ROKR E8. A spare Motorola ROKR E8 battery will ensure that you are always prepared. It can extend your talk time and reduce worry about dying Motorola ROKR E8 battery life if you are on a long call or listening to music. It's also great for safety on long trips especially when your Motorola ROKR E8 battery is dying and there is no charger around. A spare Motorola ROKR E8 battery that is charged and ready to go will do the trick.