Surface Mount Pattress box

I have a controller for my electric underfloor heating which is the same size as a single light switch / 13 amp socket. I want to use a surface mount box but the fixing mechanism is not the same as a standard pattress box. Obviously, the standard switch has two holes in it through which screws pass to screw into captive 'nuts' within the body of the pattress box. However, on the controller that I have there are no holes through which the screws can pass; rather, on the reverse there are two slots which would appear to locate on some sort of cheesehead arrangement and then twist to locate in position.
My question is, where can I find such a pattress box that would fit this controller?

Grumpy: hi & welcome I'm happy you joined the forum!

Did you have something like this in mind?

Jeffie,
all the pattress boxes I could see there on the Maplin site are, indeed, the standard ones which are available everywhere. I can see that I should post a photo as my explanation does not appear to have worked!

thanks very much for the response.
Steve

No, I got the picture now, Grumpy. I'm sorry I didn't understand you at first. Unfortunately none of my searches for this have turned up with a result that you're asking for. I will look around here in the hardware stores, and ask - and, if any usable information will be given to me, I'll place it here

Very kind - thank you very much.

Grumpy,

Would it be possible to measure and drill 2 holes that would match the standard pattress box?

that's what I'll have to do as a last resort. But I cannot believe that these controllers are not made with some proper mounting mechanism in mind but finding it is proving a bit of a bind!

Well, I'm starting to believe it because here in the hardware store they haven't even heard of it and after thorough search on the internet there are no results showing up either

Ah well, at least it shows that it's not just me that cannot find them! Many thanks for your efforts!

Yeah, but I'm thinking of it. I will look for it now every chance I get it just doesn't seem logic although results till now prove it to be so.