I thought this would be easy but it's not. I want some lengths of
what is essentially plastic angle but specifically for use as beading
along the edge of a worktop as the wall is so out of striaght that
there are gaps too large for just using silicone filler.

So - what's it called and where can I buy it? I've tried Screwfix and
can't find it there and I've Googled a bit to no avail. Maybe I just
have the wrong name for it.

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Chris Green