Need help identifying a USS-64 machine

[bubba]

Thats pretty cool.. never seen a 7 selection..

[tkaz]

The bottle viewing windows are a lot smaller too, just above the turn knobs. I wonder what the 91 stands for in the model number, that's the only one I can't make sense of.  Maybe the 7 shelves could hold 13 skinny cans or bottles each?