I've seen this on buildings but can't seem to find it for sale, or
know what it is properly called to ask for it or search for it at
screwfix.
Can anybody help and advise where I can buy it from?

Where I have run wires along and down exterior walls (e.g the wire out
to my shed) I want to get hold of some metal trim to fix over the wire
and cover it up.
Both to make it look tidier and to protect it low down from someone
catching it (it is in a narrow alley).

The stuff i have seen was just a shaped section of galved metal that
laid over the top of the wire and was nailed/screwed onto the wall on
the flats on either side.
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