Textbook M31 pattern canteen in excellent condition. The canteen is nicely marked ESB 38/39 which indicates production byEduard Sommerfeld, Berlin,the difference in years is the result of a factory mismatch made in January 1939. The strap is marked Deutsches Rotes Kreuz Kreisstelle Kassel-StadtThe canteen is simply in good complete condition and would be hard to upgrade!