XINGYHENG 20A 300W High-Power Buck Converter Module DC 6-40V to DC 1.2-36V Adjustable Constant Voltage Constant Current Power Module Charging Drive with Short Circuit Protection

Just be sure that you don't limit the current when adjusting the voltage output (unless that's what you're going for)

Seems to be perfect for my R2D2 electronics.

It definetly reduced the voltage as it was supposed to but would not pass enough current to operate even a light load, and all adjustments were checked and rechecked. It also comes with no instructions what so ever.

It worked, but I could never get it above 80W, specifically 10A at 8V, using a 20V lipo.

I am not in ebike professional of any kind I got this because I have an overabundance of power tool batteries and a few mobility scooters that need batteries so I use my power tool batteries and use the step down transformer to take 40v down 24 V and it works great but it doesn't deal well with the back voltage from releasing the throttle on the mobility scooters. . I don't know if ebikes use permanent magnet motors but mobility scooters do and I think that could be a problem. I am going to try to use this transformer for my backup power systems (UPS) stepping 40v down to 24v. It doesn't work for the UPS either. :-(

Dropped my drill bat from 18v nominal to a tolerable 14.2v for my 300w inverter. It's been running like a champ for several months now and is used everyday.

Board failed after just a few hours of use.

Works flawlessly. Used it to retard my new off road fog lights for on road use. Run them at 10v and they work great.