not available online, but plenty available in the warehouses.
This isn't available as far as I can determine. Link please?
I would check , house insurance cover before installing anything electrical especially if it link to a boiler.
It's in a cupboard. I don't see it. So I don't care :)
Got you now. I was puzzled, that's all. As a previous commentator alluded, I'm not (currently - although I have been SELECT accredited) a spark, but I have certified many installations to IEE wiring regs in the past and I still am a CEng. (formerly IEE, now IET). I hope that this explains my query & thanks for the pic!