Brand: Unknown
Keys: 41 Treble, 2 treble registers, 120 bass buttons
Serial #: 20421

Playing: Untested as I don't know how to play it. I did move both sides in and out.  You hear it and the frequency changes of course when both the treble keys are pushed and when bass keys are pressed.  Would need some sort of tune up (and maybe even minor repair) I would assume to get it playable though as it has probably "sat around" for a long time.   I seen a youtube video how inner bass button assembly gets dirty and needs to be cleaned. 

Physical condition:  Very nice overall.  Appears the trim around the grill is missing (see arrows in last photo).  Also is missing one screw holding the "door" on.  The bass keys stick down a little when pressed.  They do come back up but not good enough to rely on.  I assume must be "tuned up" or "restored" first.

Notes: Looks to have had "JOHN" embossed letters on it before they have since been removed.  (Last photo).