This US canteen 
Enameled steel canteens were not used very long by the U.S. Army and have become collectible.  During WWII U.S. canteens were normally made from stainless steel.  As stainless steel became more expensive and was already in huge demand for the making of aircraft during WWII the military looked for ways to reduce costs and preserve metals in 1942.  Their answer was a lower quality metal with a porcelain enameling which turned out to be a problem.  Due to shipping of these canteen, causing concern about the quality of the water, along with the canteens being damaged easily the army was forced to return to the stainless steel variety previously used.  
Records indicate that the U.S. Army manufactured enameled steel canteens from six manufacturers in 1942.