Strange Radiator Valve Screw

[adonis]

I need to turn on a radiator and want to remove the valve top to put a spanner on it as it as it is stiff,
however the screw holding it on looks like a security screw as it has two holes in it.
Has anyone seen these before?

 

[exedon2]

Look for 2 hole security screw screwdriver

 

[ShaunCorbs]

Yep if you get a flat headed screwdriver in / on one slot and tap it should go round etc

 

[Gasmk1]

Pin nose pliers one point in each hole

 

[adonis]

Thanks for the replies, I will try your suggestions.

 

[Sparkgap]

Was it Hoval or Ideal valves? Used to have loads of those knocking around: rectangular piece of steel with a couple of square holes in and two prongs off each end. Prongs unscrew the lockshield valve cap, square holes for adjusting/shutting the valve. Simples!