@Dave_H Thanks for the info. Like this one for example, how can that restrict flow of water in the radiator?

@Dave_H Thanks pretty sure looking at the compatibility guide that mine is this one requiring the RA adapter Do they come with an adapter or is that an addon? Also, some pictures I have seen on your...

Danfoss 013G5023 Thermostatic Radiator Head RAS-C Valve Sensor RA Connection Class A