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).
Cross-sectional diagram of a non-return valve assembly.
| Identifier | ExFiles\Box 40\4\ Scan111 | |
| Date | 14th July 1925 guessed | |
| [ "Union Nut", "Spring", "Felt", "Vent Hole", "Cap", "Piston", "Non-Return Valve" ], | ||