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I found a similar USB module on amazon. It looks extremely different but does the same exact thing. The mini USB port is used to charge the power bank and the full size usb is used to charge devices with the power bank.https://www.amazon.com/Yeeco-Ultra-small-Efficiency-Converter-Charging/dp/B00RWWYGCC/
Where can I buy that USB step up board? None of the ones I can find have a charging port for the batteries.