These are completely rebuilt Allen Organ C3 amplifiers that are in excellent working condition. Plug & Play ready, comes with all working tubes as seen for each amplifier and power plugs.
They are quiet, punchy, with a wide soundstage, strong bass and have easily outperformed many challengers in my listening room including vintage Macintosh 225, 240, etc. These amplifiers are highly rated in the audiophile community. Many close up photos, schematic details, and general history are available at Audio Karma. "The beastly beast Allen Organ C-3". Also listed under the same screen name on Audiogon.