Initially a long lever was clamped to the clutch pedal. Unfortunately, this was not convenient for other farm workers who used the tractor. The fixed lever was shortened and a sleeved joint created near the bottom. When the client drives the tractor he slides the top end of the lever over this joint to give him clutch control but when others drive it, the shortened lever does not interfere with their operation of the clutch.
The farmer could drive his tractor using his left hand to operate the clutch and found great satisfaction in being able to contribute more to the running of the farm.