of questionable merit and unknown utilty. It almost looks like it was modified for some sort of fixed installation, or voice-overs, but that's purely speculation. There's nonstandard I/O (BNC and DB25) & a dubious "remote" input (multipin barrel connector) on the back. Plus, the suitcase handle. There are too many unknowns about this unit, and it's anything but standard.
It's labelled Zetec FM-22-4, so it's a nonstandard something, but we don't know what.
The layman or person off the street wouldn't know how or why this unit was modified, or if it still functions as a standard unit would perform. At the minimum it's misrepresented, by not mentioning the obvious fact it's been modified, tho' the seller may not be aware of it.
Maybe those mods are dy-no-mite improvements on the original design, but would you want to take that chance? For the Newbie level recordist it's not recommended. Herm's a 22-4 expert, and he wouldn't touch it. What's that leave in between? Call Zetec and ask about the mods? It could be optimized as a flight data recorder, for all we know.... or for dispatch logging? Too many unknowns. It has a "Dupe" switch on the back! Sweet!
"Originally headquartered in Issaquah, Washington, Zetec created their first analog testers in small offices and even in an old dairy barn. The original testers utilized reel-to-reel recorders and simple robotic positioners, Zetec products have advanced enormously. Today, Zetec offers a full line of state-of-the-art eddy current inspection systems as well as ultrasonic testers, robotics, software, scanners and probes."