Here's a cool one - it's a patented "double back" instrument, with a secondary chamber behind the back of a regular mandolin. The idea is that if you hold it against your stomach when you play, you won't damp the vibration of the back. We're not 100% sure who built this (one suggestion is that it was built by the New Jersey-based United Guitar Company) but they do show up branded as Blue Comet, Imperial, Beltone and, as for this one, Medalist.
It's in great shape, as you can see from the photos, although it still "suffers" from its original workmanship issues - you know, rough frets, cheap tuners, non-compensated bridge, etc.
This mandolin is set up, it's playing well and it's ready to go.