Primus model 71E camping stove in where the “E” stands for the early complete set with big pan, frying pan lid, aluminum handle, loose windshield that is held inside the burner united when not attached to top as windshield/pot rest. It has the original early small key but a former owner did what Primus also did …make the key longer. A stainless steel rod was flex between the two halfs. I learned from the former owner that is was used in the Second World War so I am guesstimating this is a ca. 1938 version. The black belt is new and does the job well. The aluminum outside shows heavy weathering. Not tested but has been used not to long ago. Do check the YouTube video I found below to see some of these vintage stoves working!