Photograph showing twelve bottom tappets from a Bentley 60 No.1 Unit after a 50-hour endurance test, arranged in two columns.
| Identifier | ExFiles\Box 123\5\ scan0334 | |
| Date | 15th February 1939 guessed | |
| BENTLEY 60: No.1 UNIT. Bottom Tappets after 50 hrs. Endurance Test. | ||
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).