The FA and FB type cars had a rigid steering column, with hand throttle, ignition controls and horn button on the centre boss of the wheel. On the later FD and FE cars, a flexible joint was introduced in the steering column, which meant that these items would have to be relocated onto the dashboard.
It is believed that the earlier cars had "René Thomas" sprung spoke steering wheels, while the later cars including all the FD and FE types used 18 inch "Bluemels" wheels, as described at this link.
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