There were well over 40 different designs of diamond shaped depot plaques. or decals, during the 'sectorisation' period of British Rail between 1987 and 1997. Most of these designs were devised by the Roundel Design Group based on industry local to the depot, however some were devised locally by depot staff. The cast versions were produced by David Newton of Nottingham. They were produced in several sizes depending on their position on the vehicle. Background colour, although usually black, varied within designs. Most of these have now been removed from locomotives and rolling stock.
Here is a table of different designs known about, but not necessarily carried by locomotives or rolling stock. Some were used as signs for the depot entrance, fuel tanks or offices.
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