Textbook unissued M42 canteen marked RFI 43

Textbook M42 canteen in unissued condition. The cup is nicely marked RFI 43 which indicates production by Rudolf Fissler KG, Idar-Oberstein in 1943 which is a rather hard to find manufacturer! Typical two piece construction strap made out of smooth leather. Stone mint example which would be hard to upgrade!