From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Sample card showing two patterns of blue leather.
| Identifier | ExFiles\Box 118\1\ scan0209 | |
| Date | 18th April 1940 guessed | |
| patterns of leather | ||