Drawing of a 3½ Litre S.S. Cast Iron Brake Drum.
| Identifier | ExFiles\Box 126\5\ scan0157 | |
| Date | 8th March 1938 guessed | |
| 3½ LITRE S.S. BRAKE DRUM. C.I. 15⅛ 14¾'' 14½'' 14'' S.S.39. 1'' .825 .225 2.400 2.150 .300 5/8 3⅝ DIA 5'' Crs 16½'' DIA | ||
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).