A Kégresse track is a kind of rubber or canvas continuous track which uses a flexible belt rather than interlocking metal segments. It can be fitted to a conventional car or truck to turn it into a half-track, suitable for use over rough or soft ground. Conventional front wheels and steering are used, although skis may also be fitted. A snowmobile is a smaller ski-only type. Technology The Kégresse propulsion and suspension system incorporates an articulated bogie, fitted to the rear of the vehicle with a large drive wheel at one end, a large unpowered idler wheel at the other, and several small guide wheels in between, over which run a reinforced flexible belt. The belt is fitted with metal or rubber treads to grip the ground. It differs from conventional track systems by using a flexible belt rather than interlocking metal segments. Use in Russia The name comes from the system's inventor Adolphe Kégresse, who designed the original while working for Tsar Nicholas II of Russia between 1906 and 1916. He applied it to several cars in the royal garage including Rolls-Royce cars and Packard trucks. The Russian army also fitted the system to a number of their Austin Armoured Cars. Further development in France After the Russian Revolution Adolphe Kégresse returned to his native country, France, where the system was used on Citroën cars between 1921 and 1937 for off-road and military vehicles. A series of expeditions across the undeveloped parts of Asia, America, and Africa was undertaken by Citroën, demonstrating the all-terrain capabilities of these vehicles. In World War II, both sides used this system in the war effort. In the 1920s, the U.S. Army purchased several Citroën-Kégresse vehicles for evaluation and then purchased a licence to produce them. This resulted in the Army Ordnance Department building a prototype in 1939. In December 1942, it went into production with the M2 Half Track Car and M3 Half-track versions. The Nazis also captured many of these Citroën half-track vehicles and armored them for their own use. Use in Great Britain An 30 cwt armored personnel carrier called "Burford-Kégress" was built by the British firm Burford on the basis of its four-axle trucks with wheel formula 4 × 2. It was equipped with rear-axle powered Kégresse tracks produced under license from the French company Citroën. Finished in 1926, the prototype passed trials, the results of which were positively received