5 decal variants:
1. Bücker 131D, LKS 7, Luftwaffe, Wien-Seyring 1942
2. Bücker 131D, FFS A/B 14, Luftwaffe, Klagenfurt 1941
3. Bücker 131D, RHAF, II. Tactical Rec. Squadron, Hungary 1939
4. Bücker 131D, 4.FFS A/B 52, Luftwaffe, Danzig, Summer 1944
5. Bücker 131D, Sch/FAR 71, Luftwaffe, Prostejov 1941
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.