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).
Rubbing of a 7x18 Dunlop tyre tread pattern with a special outside edge.
| Identifier | ExFiles\Box 157\1\ scan0357 | |
| Date | 1st May 1936 guessed | |
| HJR/pru PM 7x18 Dunlop. Tyr. Special outside edge. Outside B 31 EX @ 35 lbs / □'' A/ED{J. L. Edwards} | ||