The Kanonenjagdpanzer (KaJaPa) also known as Jagdpanzer Kanone 90mm, was a German Cold War tank destroyer equipped with a 90mm anti-tank gun taken from obsolete M47 Patton tanks. Its design was very similar to that of the World War II Jagdpanzer IV. The Kanonenjagdpanzer was a highly mobile vehicle, its survivability based on its mobility and its low profile. Its hull consisted of welded steel with a maximum thickness of 50 mm. It carried a crew of four: commander, driver, gunner and loader. Since the Kanonenjagdpanzer followed the casemate design of most World War II tank destroyers, the gun was fixed within the casemate, located a little right from the center. The 90 mm gun could only traverse 15° to the sides and elevate from - 8° to +15°. It carried 51 90 mm rounds for the main gun and 4,000 7.62 mm rounds for the two MG3s. The Kanonenjagdpanzer had NBC protection and night-fighting ability.
The first prototypes of the Kanonenjagdpanzer were built in 1960 by Hanomag and Henschel for West Germany and by MOWAG for Switzerland. Between 1966 and 1967, 770 units were built for the Bundeswehr, 385 by Hanomag and 385 by Henschel. When the Soviets began deploying their T-64 and T-72 main battle tanks, the 90 mm gun was not capable of engaging them in long-range combat and the Kanonenjagdpanzer became obsolete. Although the producers claimed it could be rearmed with a 105 mm gun, between 1983 and 1985, 163 of these tank destroyers were converted into Raketenjagdpanzer Jaguar 2 anti-tank guided missile carriers by removing the gun, adding a roof-mounted TOW missile launcher and fastening further spaced and perforated armour on the hull. Some others were refitted into artillery observation vehicles by removing the main gun, so called Beobachtungspanzer, which served most particularly in the mortar units.