Original Item: Only One Available. This is an original German WWII M31 field canteen, or Feldflasche 31, retaining its felt cover, leather carrying harness, screw cap, and steel drinking cup.

Although wartime collectors sometimes use terms such as “M42” for later steel-bodied examples, the canteen remained fundamentally part of the M31 field flask system. The principal differences are in the materials and construction used as wartime shortages and production changes increasingly replaced the aluminum components seen on earlier examples.

Early M31 canteens were typically fitted with an aluminum bottle and aluminum drinking cup, together with a brown felt insulating cover and leather harness. As the war progressed, German manufacturers increasingly substituted steel for aluminum. This example represents that later wartime development, with an enameled steel bottle and painted steel cup, while still retaining the familiar M31 configuration.

The exposed neck of the bottle shows a deep red-brown enamel finish, a feature encountered on wartime steel canteens. The bottle remains enclosed in its coarse brown felt cover, secured by metal snap fasteners, while the brown leather harness incorporates the vertical retaining strap, buckle, and leather loops typical of the M31 carrying arrangement.

The drinking cup retains much of its olive-brown painted finish and is fitted with the characteristic folding wire handles. The cup handle bracket is hand-marked SP., likely a personal or ownership marking. Beneath this is the factory marking CFL 43, identifying the cup as a 1943 product of Carl Feldhaus Aluminium- und Metallwerke, Lüdenscheid. The screw cap is made of bakelite, and bears an integral molded symbol/code appearing as 4A/S. The “S” in such material codes might be associated with the use of sawdust or wood flour as the filler material in the phenolic resin. The precise manufacturer represented by the 4A portion cannot be confirmed.

The canteen remains in good condition. The brown felt cover shows expected wear and scattered fiber loss from age and use, but remains substantially intact and properly fitted around the bottle.

The leather harness is complete but shows significant age, including surface cracking, dryness, general wear, and substantial leather blooming, particularly along the vertical retaining strap and leather loops. Leather blooming is the whitish or cloudy surface deposit that can form when natural oils, fats, or waxes within old leather migrate to the surface over time, often as a result of age and changes in temperature or humidity. It is a common phenomenon on period leather and should not be confused with mold. The harness remains an appealing original component, but due to its age and dryness, it should be handled with appropriate care.

The painted steel cup remains quite presentable, retaining a good amount of its original olive-brown finish with scattered scratches, edge wear, and oxidation. Both folding wire handles are present, and the hand-applied “SP.” marking remains clearly visible.

The red-brown enamel finish on the bottle is particularly evident around the exposed neck. There is expected wear and oxidation around the threaded area, but the surviving enamel remains strong and makes the later wartime steel construction readily apparent. The screw cap remains present with age and oxidation around its attachment point.

As with any original WWII canteen, it has not been tested for water tightness and is intended for historical display or collecting rather than modern drinking use.

The Feldflasche 31 was introduced in 1931 and became the standard German military water bottle throughout WWII. Its basic arrangement consisted of a roughly 0.8-liter bottle, insulating cover, leather suspension harness, screw cap, and detachable drinking cup.

The earliest and prewar M31 canteens are generally associated with aluminum bottles and cups, materials that were lightweight, corrosion-resistant, and well suited to field use. During WWII, however, aluminum became increasingly valuable for other military applications, particularly aircraft production. German equipment manufacturers therefore began making greater use of steel and other substitute materials.

Later-war M31 canteens consequently appear in numerous combinations, including steel bottles, painted or enameled finishes, steel cups, modified hardware, and other production variations. These changes did not create an entirely new official canteen model in the same sense as a formal redesign; rather, they were wartime production developments within the continuing M31 system.