A few days ago I found this piece of surplus in eBay. I bided it and finally got it. Nice equipment from the past. I wired it for YAESU, no big deal, and I put it on the air. It works perfectly. Well, it needs a bit more mice gain and the transmit audio is a bit of small bandwidth but no other problem. It is a proper headset for contesting or other heavy traffic operations in SSB. In construction it looks like a Roll Royce vs a sevy, compared with the trendy Heill sets. It is really amazing how they were manufacturing such things in the past.