This is a shoulder carried valveless horn / bugle in the key of Eb.  I call it a Rhein Horn because I have seen bands of these kinds of horns (usually on bicycles) in towns along the Rhein River in Germany. They are made in several sizes - this one plays like a baritone or trombone with an 8" bell.  The progression of notes available are: Eb-G-Bb-Eb.  There is a mechanism on the leadpipe for substancial flexibility in positioning the mouthpiece.  It is played in ensemble with various other sized valveless horns - creating  lovely Tyrolean -style music.