Featuring four premium 18650 cells and an integrated PCB, this power solution delivers a steady 7. 4V output with a robust 5200mAh capacity. 4V 5200mAh li-ion battery pack, with high safety, real capacity, and low resistance. Ideal for Bluetooth speakers, flashlights, and medical equipment. The included 2-pin wire connector ensures quick and secure connectivity for custom circuits, prototypes, and innovative electronic builds, making it the ideal. This Li-ion Rechargeable Battery Pack has a nominal voltage of 7. The battery pack has a built-in BMS that protects the battery. For maximum lasting time, KinStar 7.