The point is, if you take a plug-in module apart, you end up
with exactly the item in your photograph -- that's just the top
half of the plug-in module. Plug-in modules are often cheaper
(although not from that supplier).

Pulled a plug-in module apart and confirmed this. "wired" version comes with
a mounting bracket which could be useful though.

They have a 20mm fuse on the front, but MCB's are probably

Didn't know this - do now, thanks.

Alan.