2PCS USB Buck Boost Converter Adjustable Step UP Step Down Power Supply Module Voltage Regulator DC-DC 5V to 3.3V 9V 12V 18V 24V

I used this for a Ring doorbell (after of course putting it in an enclosure and weather proofing it.) I also ran a usb bulb socket adapter from my outdoor wall light in-order to get the necessary USB port. Once the voltage was upped to 24 volts the Ring doorbell went from 77% to 100% in less then an hour. Completely blows away the terrible solar panels. Easy to use, just press the button to turn it on and use the dial to set the voltage. A perfect setup until I find the time to run an ethernet cable and normal doorbell wiring.

I bought it two pack of these boards to provide 20 volt power to the LED backlighting of a 5-in diagonal embedded display. It worked as I had hoped and I have no complaints. I do wish it had a mounting case or mounting holes but that's not a deal breaker me. It works. What else can I say?

The voltage was accurate, well within an acceptable range, seems like a great deal as well. Haven’t tested the micro usb yet, but seems high quality for $9.

Needed to bring power from a battery bank from 5v to 3.3v but after two minutes it gets super hot and starts changing voltage causing my device to restart

Sweet! Perfect for bench testing low voltage stuff and drone parts.... I LOVE THESE THINGS!

connect it with 5v to get 18v, become very hot. but for step down working good

Used this to run 2 fans at 12 volts. First one died after a few hours. Set up the second one ... died a few hours later. Bad quality control.

This product works but as soon as I tried to use the micro usb port it snapped off. I was careful when plugging it up but the soldering wasn't good at all. The unit will still work but not with micro usb now.