The 2S 3A Li-ion Lithium Battery 7.4V–8.4V 18650 Charger Protection Board Module ensures safe charging and discharging for 2-series Li-ion battery packs. It features built-in overcharge, over-discharge, and short-circuit protection to prolong battery life and maintain performance. Compact and durable, it’s ideal for battery-powered DIY projects, e-bikes, power banks, and other electronics.