Tropical M31 1L Labeflasche marked CFL 41

Textbook “Tropical” M31 (Alum.) 1L Labeflasche in excellent condition. The flask and the cover are both nicely marked CFL 41 which indicates production by Carl Feldhaus Aluminium-und Metallwerke, Lüdenscheid in 1941. The canteen comes in a typical configuration with webbing straps and a unmarked black bakelite cup. Textbook example which would be hard to upgrade!