Mini Li-Ion Battery Charging Board 3.7V 4.2V 18650 Charging Protection Board

1.Ultra-small size design, easily embedded in smart wearable, micro-drone and other compact space. This 3.7V Li-ion battery charging pad is easily embedded in compact spaces with its ultra-small design for smart wearables, micro drones, loT devices, electric mosquito swatters, etc., and it can even be tucked directly into the space of a usual charging cable head.

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