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).
Comparison of deflection and permanent set under load for Old style H section levers versus Oval section levers.
| Identifier | ExFiles\Box 38\1\ Scan071 | |
| Date | 19th August 1920 | |
| Load lbs | Old style H section levers | Oval section levers | Deflection | Per. Set | Deflection | Per. Set 1000 | .420" | | .390" | Nil 1500 | .615" | | .539" | Nil 2000 | .866" | .090" | .682" | Nil 2500 | 1.264" | .380" | .843" | .040" 2700 | continuous | 1.410" | .944" | .110" 3000 | | | 1.250" | .330" 3200 | | | 1.610" | .530" X3465 7 File Pendulum Levers 19/8/20 | ||