Duracell Recharge Ultra AAA 850mAh Rechargeable batteries are a great product for high drain devices and items that are in constant use. These batteries combine the convenience and power of an alkaline battery with the money saving and environmental benefits of a rechargeable battery. The high capacity of these batteries means they can be used in various devices such as digital cameras, hand held video games and wireless mice to name a few . These Duracell Duralock rechargeable batteries are guaranteed to last 5 years and with the Duralock Power Preserveï¾™ Technology the batteries holds a charge for up to 1 year when in storage. Impressive!