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).
Specification sheet for Triple Shell Motor Oil.
| Identifier | ExFiles\Box 20\4\ Scan058 | |
| Date | 16th April 1930 | |
| TRIPLE SHELL MOTOR OIL (Current specification 16/4/30). Specific Gravity @ 60°F .935 Flash point (closed) :F 385 Viscosity R.1 @ 70°F secs. 3000 " " @ 140°F " 235 " " @ 200°F " 73 Pour Test °F 15 | ||