Anyone know what this skirting top section is called?

[Kaymo]

Hi all,
Pic below.

Much of the skirting in my house is like this. There is a flat board stuck to the wall and this sits on top, in most cases its pinned to the board below. I would like to buy some to replace the top section in one room, but I cannot find anything similar online. Doesn't have to be the same profile as I can just replace it all

Its effectively just architrave I suppose, but with a section routered out to allow it to overlap the flat board. Maybe that is all it is and if I am stuck I can probably just replace it with architrave, but thought it worth a check to see if anyone had come across this before?

 

[freddiemercurystwin]

The photo is out of focus.

 

[Kaymo]

The photo below might be a bit better, external profile that was blurred isn't that important anyway, its the cutaway so that it sits on top of a flat board that I wanted to show.

I think I have found what it is now anyway. I think it is 'rebated dado rail'. Found a few examples of it online and it usually goes at the top of wood panelling, but it seems whoever did the skirting in my house years back must have used it to top off shorter boards to make skirting.