2X(10PCS Modulo Scheda di Ricarica Batteria Litio 3.7V 4.2V 18650 Batteria 2117

The green light is high and the power red light is low, indicating that the power has been connected. The B+B - end is connected to the battery, and the green light out. The power red light remains on, indicating that the battery is charging.

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