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).
The specifications for a 12-inch diameter clutch with dampered sprung drive.
| Identifier | ExFiles\Box 128\2\ scan0223 | |
| Date | 12th June 1934 guessed | |
| Sev X2200 Clutch File Long 12" Dia Clutch This clutch has a dampered sprung drive is to be set at 139 lbs ft / degree driving load 9 lbs ft damping load Allowed movement ± 2¼° [Crossed out signature: Weald Bentley Front Axle] 2340 181 went through on Production. Lod. | ||