Small vintage amp from the late fifties or early sixties.  We don't know much about this amp, but it was probablly made by Magnatone, Harmony, Valco, or someone like that and branded with the Stewart name.  All tube amp, hand wired with cloth covered wire.  One 8" speaker.  Hard to say if it is original.  Uses one 6X4, one 6BQ5, and two 6AV6.  The tremelo sounds great. Our amp tech has brought this little gem back to life. This amp has a clean bill of health. It will make some studio very happy.