SUREFIRE SureFire Sf123A Bulk Box 400 Cells Optimized for use in SureFire flashlights, SureFire high-performance lithium batteries pack a lot of power into a very small package. And unlike alkaline batteries, SureFire provide 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 lithium batteries