Interesting design - it looks to possibly be based on the Hirsbrunner (?) judging by where the slides are positioned and the fact the the bottom bow connects extremely high up to the horn/bell. Hirsbrunners certainly don't have 11" bells, though, to my knowledge. Too bad the website doesn't have any more info on the specs.
Based on the photos alone, this is definitely a horn I wouldn't stand on its bell!
Sean Kissane
Low Brass Specialist, Paige's Music
Principal Euphonium, Indianapolis Brass Choir
Principal Euphonium, Crossroads Brass Band