In 1966 the first Unimog 421 was produced. The Unimog 421 was a Unimog with a 4 cylinder motor type OM 621. The 421 was designed to improve the 411 with more comfort for the driver. The cabin was mostly improved with features such as more comfortable chairs, more field of view and a better cushioned cabin. The sales of the Unimog 421 showed that this model was another success of Mercedes. In 1971 the 150.000th Unimog was produced. Because of the compact shape, the 421 was ideal for municipality work. Alone more then 12.000 municipalities in Europe used and bought the yellow/orange Unimog.