Switzerland received the license to build the MS.406 in 1938 and named it D-3800. A pre-production of eight machines was manufactured at Adolph Saurer AG. In addition to the new EW-V3 adjustable propeller from Escher-Wyss, Swiss instruments and weapons were also installed. Pre-production was followed by 74 aircraft by August 1940, which were manufactured by the Eidgenössische Konstruktionswerkstätte Thun and Emmen and the Dornierwerke Altenrhein. The Hispano-Suiza engines were supplied by Saurer and SLM. In 1942, two more machines were assembled from leftover parts. At the end of the war, most of the D-3800s served as trainers and were decommissioned in 1954. In 1941, Switzerland received an unfinished 412 and modified it into the D-3801 by Eidg. Flugzeugwerke (F + W) Emmen, Doflug Altenrhein and SWS, Schlieren. By 1945, 207 aircraft of this type had been produced. This fleet of aircraft formed the mainstay of the Swiss Air Force during active service 1939-1945. Flight performance: V max. horizontal 535 km/h; max. climb rate 16.2 m/s; service ceiling 10,800 m a.s.l.; flight duration 1 hr 35 min; range 600 km.