The pressure switch it has on it is for toys and the expansion tank, with the factory settings it starts and stops constantly, I removed those 2, put in a proper pressure control and it works just fine. I bought two, connected them to a low-pressure solar hot and cold system, and I am satisfied with their performance. Fair price too.

Very good, simple, cheap (I got it for €58), compact, it also has a small expansion tank (IT'S NOT 45 liters guys, change it! It's 1 liter!) to take up the system's slack, it also has a built-in check valve, which is a big plus, but that's about it. It doesn't deliver the numbers it claims, only up to 2.2 bar, on the device itself, barely and without a manometer. Also, the pressure switch needs adjustment (which the clever Chinese have sealed with paint...) because it does quick restarts with the initial setting which is well below 1.5 bar, while if you overdo it, it starts working continuously without any tap open because it simply can't increase the pressure any further (so turn it back half a turn or until it stops asking). Prefer something better if you want more bar. If 2 bar is enough for you, go for it because it does a good job along with the built-in one-liter tank it has and it's very cheap.