Honbay 2PCS DC-DC Step-up Module XL6009 DC to DC Input 3V-32V to Output 5V-35V Boost Converter Module

I needed this to boost 9V to ~20V for a portable speaker project, needed to up the voltage from my USB PowerDelivery board which provides 9V to ~20V for the battery charging board. This does the trick very well. It does get quite hot and I am sure is not the most efficient thing in the world, but for my use case it was perfect. Will buy again if I have another need in the future.

It does step up the voltage but I was powering it by USB 5 volts and trying to get 20 volts out but what I found was depending on how much current you're pulling the voltage will change so it seems like the potentiometer dial is more a proportional change rather than an absolute voltage output so if your input is sagging your output will sag too. It didn't solve my application, unfortunately.

Below 8 volts it doesn't seem to work. Above 8 volts it seems to work fine.Trying to convert solar panel 6-9v output to 12v

I used one of these to step up a Ryobi 18V battery to 30V to run a reclining couch that is in the middle of the room so I don't need a power cord running to it. Works perfectly and I only have to swap the 9ah battery out every couple of weeks with a fresh one.

The voltage climbs and spikes. You'll fry your stuff. Par for the course for Amazon these days and they're twice as expensive as Banggood or eBay. Not worth my time to ship back. Amazon has no quality assurance or standards and it's not really much faster, if at all anymore.This party is dead. Move on. There are better options everywhere.