With the introduction of the 406-series in 1962, Daimler-Benz laid the foundation for a completely new Unimog model family, the 406-based medium series (in the 1960s known as "heavy" series). It was produced until 1994. Unimogs belonging to the medium series are the series 403, 413, 406, 416, 426, and 419. These models were offered with three different wheelbases (2,380 mm, 2,900 mm, 3,400 mm) and two engines, the straight-four and straight-six direct injected Diesel engines OM 314 and OM 352, ranging from 54 DIN-PS to 110 DIN-PS (40 kW – 81 kW). The light series 421 and 431 share their frame design with the 411-series, but borrow their drivetrain and cab design from the 406-series, which is why they also count as 406-related Unimogs.