At the beginning of the 1960s, there was an urgent need for suitable vehicles to transport the armoured infantry. In addition to the American M-113, prototypes from SAURER and MOWAG were also tested, but unfortunately neither was sufficiently mature.

In the end, the decision was made in favour of the M-113 because the technical and financial risks associated with the Swiss prototypes being tested were considered too high.

They relied on the troop carrier, which had already been produced thousands of times in the USA and could accommodate a crew of 3 and 7 grenadiers. In 1963, in a first tranche of the armament programme, the Swiss Army procured about 800 infantry fighting vehicles in combat version, as transmission tanks, armoured engineer vehicles, command tanks and other versions.