Stereo preamplifier with scope option, top of the 3300/3600 preamp family.
Solid-state: check autoformer/Power Guard boards and the original output devices; re-professional recap is expected at this age.
Marks that can be entered for this maker: Serial number, Model / catalogue number, British capacitor code (Hunts, Mullard), Japanese capacitor code (Nichicon, Chemi-Con, ELNA), EIA component code, Chassis / platter stamp, Version & era marker.
The introduction year is not documented, so the model narrows nothing.
Sold-listing reading: fair $312, good $312, excellent $312 USD · 1 sold listings (thin sample — indicative only) · as of 2013-12 – 2013-12. Only 1 sold listing(s) found in the eBay SOLD table (['2013-12-03'], https://classicreceivers.com/vintage-receiver-values — below the 3-observation threshold), so the price is an estimate/anchor, not a market average.