Whats this on my Radiator valve

[nyck]

No idea, it's just the tail,

Is it really:

Untitled

• Charnwood
• 12 Nov 2013
• 1

Comap Westco do not put thread seal of any type on their rad valves. If they did, both valves would have it, and the picture from their website would show it.
I will ask again: from where were they purchased?

Gumtree someone local

that is just dust on the thread

 

[jhiker]

To my eye they look like different threads. The one on the left is a taper thread and the one on the right looks like a parallel thread.
They supposed to be like that?

 

[GavThePlumber]

I will ask again: from where were they purchased?

Gumtree someone local

May i ask why you would buy them second hand? these are £8, eight quid! valves.
You are not even covered by the manufacturers warranty either now, should any damage happen to your system/boiler due to a manufacture fault.