Drawing of a valve spring support with dimensions labelled A, B, C, and D.
| Identifier | ExFiles\Box 80\3\ scan0208 | |
| Date | 7th April 1920 | |
| y Valve Spring Support. A B C D S N RECEIVED APR 7 1920 | ||
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).