They were made by Yorkshire Copper and called "Biflow Valves".
Haven't seen them for years. They worked well so long as the internal
pipe was fitted. Googled but no results.






Just been reading about how to remove the radiator. I never had a problem.
Move rad to one side after unscrewing valve and then unscrew the internal
pipe - which on all of mine were nylon - self threated into the valve.
Easily done with pliers.