Review on DROK 300001 Micro LED DC-DC Digital Boost Voltage Converter Adjustable Volt Regulator Board Module Power Supply Transformer by Michael Copeland

Screw terminals are fairly cheap hence 4 stars instead of 5. It works well at a range of voltages and I've checked with my DMM that the reading is accurate. The other commenters are right though, it's quite hard to get the thing as the pot is pretty cheap too. I've had a couple of times where I reduced the voltage and the output actually went up quite a bit. This will never be enough to fry most circuits, but I'd recommend dialing it in with a DMM and then hooking up your circuit if you have something particularly sensitive.