Around the house we have those kinda white bell-shaped TRVs with the black ribbed ring you twist which kept 2 fitting lugs withdrawn (before that part of the mechanism stopped working). They look like RAS-D 2910 or 5150 on the internet, what's the difference and is there a newer equivalent that uses the same fitting as 2910 searches comes up with a more modern-looking TRV. All pins work ok.
