# The Traffic Signs Regulations and General Directions 2016, Paragraph 8

Extent: E+W+S

(1) The back of a sign must be coloured grey, red, white, black or yellow, except that—
(a) information about sites for placing and the ownership of the sign may be indicated on the back of the sign in characters not exceeding—
(i) 50 mm in height, where they are shown in a contrasting colour; or
(ii) 80 mm in height, where they are embossed in the same colour; and
(b) information about the manufacture of the sign required in order to comply with—
(i) British Standard BS EN 12899-1:2007; or
(ii) a corresponding EEA Standard,
occupying an area not exceeding 30 square centimetres, may be indicated on the back of the sign in characters not exceeding 5 mm in height.
(2) The sign may be mounted on an object of the size, colour and type of the sign provided for at item 4 of the sign table in Part 6.

---
Source: https://www.legislation.gov.uk/uksi/2016/362/schedule/13/part/12/paragraph/8 (the official version)
Page: https://openlegislation.uk/traffic-signs-regulations-and-general-directions-2016/schedule-13/part-12/paragraph-8
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.