In 1934 there were delays in design and production for what would be the Panzer III and IV tanks. The temporary solution was the Panzer II or Panzerkampfwagen II (PzKpfw). It was a larger version of the Panzer I but with a 20 mm anti-tank gun. The Panzer II was in production from 1937 to 1943 and remained in service until 1945. The Ausf. C was the most produced variant of the Panzer II. The Panzer II chassis was used to produce several other types of tanks.