This is a apparently Unique, Dueber, Hunter Case. Unique because it appears to be made from Aluminium! First, the Case Engraving from the Side.

Below is the Inside of the Dust Cover.

The Dueber Trade Mark is also unique & the Serial # is about two digits less than seen on most Dueber Hunter Cases.
         Below is the Back Cover, Engraved w/ a Steamship. The retaining screw on the stem seems to be wielded tight & is immovable which is a common occurrence when Iron or Steel is in contact with Aluminium. 

Below is the Front Cover, Engraved w/ an Empty Shield.  I've mounted a "Menlo Park", HN4L-A, 17 Jewel, Movement in this case because I believe both were manufactured around the same time.                                    

Case shows Carry Ware but still shines like the day it was made. At the time this case was made the price of Aluminium had dropped below that of Gold & Silver which made it economically possible to use it in the manufacture of Watch Cases. Two discoveries, made in the late 1880's, made refining Aluminium from Bauxite more efficient & therefore cheaper. Before that Aluminium was so costly that Napoleon III had Dinner Plates made from it so as to impress his guests with the opulence of his Court.