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).
Photograph of a chrome-plated hexagonal switch knob with a 'B' logo.
| Identifier | ExFiles\Box 3\4\ 04-page427 | |
| Date | 1st February 1936 guessed | |
| B ON OFF | ||