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).
Special 1.5 value ballast resistance for car 18-EX.
| Identifier | ExFiles\Box 168a\5\ img029 | |
| Date | 18th December 1928 guessed | |
| X7720 SPECIAL 1 1/2 VALUE BALLAST RESISTANCE Details of ballast given to RJA. for 18-EX car in France :- 29" of 33 S.W.G. nickel wire. EFC. | ||