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).
Blueprint showing a cross-section of a valve assembly and guide.
| Identifier | ExFiles\Box 86\1\ scan0042 | |
| Date | 4th December 1933 guessed | |
| [ "L_E C3673", "1.3" DIA", "1.5" DIA", "A", "lve" ], | ||