4 decal variants:
1. C-4, 2nd Air Division České Budějovice, Staff Capt. Pošta, Plzeň 1946
2. C-4.6, Cpt. M. Liškutín, air show Bystřice nad Hos., September 1947
3. C.16, VLU, Prostějov 1947
4. C-104, OK-AQP, Czechoslovak Aeroclub, 1953
During 1936, was produced Bü 131B with powerful 105hp Hirth HM 504A-2 engine. Most produced was the version D. The aircraft was used by Luftwaffe as training, also by night ground-attack. Was also exported in many countries - Japan, Switzerland, Spain, Yugoslavia, Romania and Bulgaria. Under licence was built in Japan and after WWII also in Spain-CASA and Czechoslovakia as C-104 trainer with Walter Minor 4-III.