Is there such a thing pl?
Background is that I want to mount the receiver for another wireless thermostat (after success with 2 aged relatives thanks to advice here). The cable's all on the surface so I thought I could just use a pattress. No go: the (industry standard) backplate is too small for that. It does work with a metal 75 mm "back box" (ie the sort you plaster in for flush mounting). But I can't find the surface mounting equivalent of that. Some manufacturers refer to a "conduit box" but I've not found one in plastic which is 75 mm as opposed to 86 or 87 mm and have square eyes from looking.