Always Be Prepared. Optimized for use in SureFire flashlights, SureFire 123A high-performance lithium batteries pack a lot of power into a very small package. And unlike alkaline batteries, SureFire batteries have a 10-year shelf life, which means they will be ready when you need them, every time. Trust in the power and durability of SureFire batteries. FeaturesHigh-performance batteries, optimized for high-drain use in flashlights10-year shelf life makes SureFire 123As an excellent option for emergency power needsWide temperature tolerance prevents degradation when in use or when stored Key AttributesBATTERY TYPE - 123AVOLTAGE - 3 voltsCAPACITY - 1,550 mAhENERGY - 4.65 WhWEIGHT - 17 gramsLITHIUM CONTENT - 0.6 grams