In the early 1960s, the 75-mm gun with a muzzle velocity of 1,000 m/s was deemed outdated. The vehicle received the new 90-mm F3 gun that used more powerful HEAT shells. This modernization did not require any significant changes to the turret or vehicle design. The first vehicles were manufactured in February, 1967. The existing vehicles underwent the gun modernization as well.
The technical characteristics shown are for the Siege mode
Characteristics are specified for a vehicle with crew members trained to 100%.