Paragraph 8 F1
A border may be displayed on a registration plate where the border is—
(a)
permanently marked;
(b)
non-retroreflecting;
(c)
of a single shade of non-retroreflecting colour without any design, pattern or texture;
(d)
positioned no closer than 10 millimetres from the edge of any character of the registration mark;
(e)
not positioned above any other markings; and
(f)
no more than 5 millimetres in width.