Features of TENERGY RCR123A LI-ION Battery Charger: - Designed to work with Fenix flashlights. - Four rechargeable batteries included. - Smart, build-in microprocessor automatically switch off when batteries are fully charged. - Safe, build-in IC provides various protection, Thermal protection, Overcharge protection, Short-circuit protection, mechanical and electrical protection against reversal polarity and auto defective battery identification. - Convenient, 12V car cigarette lighter plug for on the road charging. - Compact ( 2.5 x 4 x 1 inch ), Light weight ( 5 oz only ), include charger and all accessories. - Charge 1 or 2 RCR123A from 1.5 hours to 3 hours. Peak voltage of 3.0V Li-Ion will be 3.60V after fully charged. - WARNING: This charger only works with RCR123A 900mAh and not compatible with RCR123A 750mAh batteries