I replaced the automatic air vents in the radiator system during maintenance to get it running again after many years of disuse. It appears to be of good quality and works well; time will tell how long it will last. It vented the system during filling without releasing a drop of water when it was full. The old one, along with the air, would also spit out quite a few drops of water...

easy installation, immediate operation!
it needs a small basin under the valve on the radiator for the little water that will run,
with the body valve closed so we don't fill with water and of course the thermostat closed.
I tightened it by hand very easily (it has a "stop" nut) to keep the valve in the correct position - that is, up - and tightened correctly! I recommend it without a second thought!
I am on the top floor and unfortunately had air in the radiators very often, finally I am saved!

First of all, it immediately worked on the installed boiler water heater.
I could hear the air coming out as soon as I replaced the old one.

Secondly, it is very beautiful. No comparison to the others on the market.

Thirdly, it has a flange on top and does not require Teflon.

Flawless.