DORHEA LM2596S Driver DC-DC Constant Current Module, 7V-35V Step-Down CC/CV Power Supply Module, 2A/3A MAX Output Current, UL Listed

They seem to work just fine. As with all things in life. Verify. In my scenario, 13v down to 5.6v, they are good for about 1.5 amps with a small heat sink on the chip and another on the inductor. I put thes on a 5v 1.5 amp load and then set them so that the current starts to roll off and drop the voltage at that point. This way your entire world doesn't melt down and destroy itself. Personally, when I look at these kinds of things, I always cut the marketing numbers by at least half. The math on these actually seems to work when constrained by this kind of marketing to real life math.

Voltage and current and full charge indicator. Main point I got these was for the current adjustment, to turn down for less heat on projects and testing works good. Form factors a bit large wish there was a smaller unit size is every thing when DIY projects.. Also going to test if the full charge indictor stops the voltage flow for charging batteries ( would like to be able to walk away for coffee or other things and not have to worry)If so this will be worth the $

You definitely need heat sinks for the MOSFET on this modulator. I used it with a old laptop adapter which is 19 volts at 3.3 amps...I set the module at12 volts and the MOSFET gets hot, not super hot, but hot at 1 amp.

I got a package of 5 and was not able to set the current limit on any of them. I adjusted the current set potentiometer from one extreme to the other, but the short circuit current remained stuck at 2.5+ Amps. Can not be used for battery charging, but only as variable voltage power supplies. Can't argue with a 4.5 star rating - maybe I just got some from a bad batch...?

These were easy to solder to and adjust voltage using an external potentiometer.