From Maclan Racing:
With this cable, one can connect Maclan ESCs that have a micro usb port, to smartphones and tablets that also utilize a micro usb port. In addition, this allows a direct connection from the Maclan micro usb style ESCs to our ProLink programming card. This is an improved solution to the original OTG cable adapter (MCL4053).
Note: This cable is directional. It will not function properly if not connected in the correct orientation. Please notice the positioning of the letter B in relation to the metal portion of the connector.
Connector #1 – Letter “B” located closer to the metal portion of the connector.
Connector #2 – The USB symbol is closer to the metal portion of the connector.
If you are connecting the Maclan ESC to a micro USB tablet, please insert connector #1 into the tablet, and connector #2 into the ESC. (See photo below):
If you are connecting the ESC to a ProLink, please insert connector #1 into the ESC, and connector #2 into the ProLink. (See diagram below):