This has been my EDC for the past two years or so. A colleague gifted it to my grandfather decades ago and he eventually gave it to me. It shows some wear but I manage to keep a good edge on it and it's pretty robust. The blade is just shy of 4 inches with a lug on the spine that I don't know the purpose of, it's not a bottle opener. The manufacturer's mark(?) is engraved near the base of the blade. There's a hole for a lanyard on the base of the grip. The grip panels are a red laminate and is pinned to the grip with brass pins. The grip is made of five steel panels and appeared pinned and welded together, there's 7 heat marks on the metal grip that look like pins were welded in and ground down. This knife has always been a mystery to me. I have no idea what it is or where it came from. Any ideas?