Power Your XSC. Specifically designed to power the SureFire XSC micro-compact Weapon Light series, the SureFire B12 is a quick-detach, rechargeable lithium-polymer battery that can be swapped quickly without removing the XSC from the host pistol. The compact B12 powers the 350-lumen XSC for up to 30 minutes. Its charge status can be checked easily by pressing the push-button fuel gauge switch on the side of the battery and viewing the green, yellow, and red LED indicators.