SFLFP123 batteries are rechargeable and reusable, saving you hundreds over 123A lithium primary batteries SFLFP123 batteries are better for the environment because they contain no hazardous heavy metals Includes two-bay charger for easy, convenient recharging at home or on the go *It should be noted that these LFP rechargeable batteries have significantly less run time than their disposable counterparts Every SFLFP123-KIT includes two Lithium Iron Phosphate (LiFePO4) 450mAh 3.2V rechargeable cells, a two-bay battery charger, and a MICRO-USB to USB-A cable Smart, internal circuitry automatically terminates charge cycle when cells are at full capacity Safety design features provide protection from overcharge, short-circuit, and reverse polarity Charge one or two SFLFP123 from 1.5 hours to 3 hours. Charge termination occurs at 3.65V typical Manufactured in China