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).
Photograph showing the rear suspension of a Delaunay-Belleville car with RETRAC oil springs attached to platform springs.
| Identifier | ExFiles\Box 46\1\ Scan136 | |
| Date | 1st January 1918 | |
| Rear Suspension of Delaunay-Belleville Car, with RETRAC Oil SPRINGS attached to Platform Springs. 54-943 N.Y. 1918 THE RETRAC CO. OIL SPRINGS | ||