9V step-up 3-speed Stepless Speed Regulation Motor Controller Fan Control Board

Gear: the red light for 5v in gear 1 is on, the green light for 7v in gear 2 is on, and the blue light for 9v in gear 3 is on. Input: type-c 5v. Connected to a 3.7v lithium battery with a charging power of 5w, supporting simultaneous charging and discharging.

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