I had the castle nut adaptor on one loosen up after riding around with me in a backpack on both a motorcycle and in the floorboard of a truck. That’s partly my fault because the folks who installed it for me didn’t loc-tite the little set screw that is supposed to hold the castle nut adaptor in place.
Compared to an akm74/AK100 series folding stock it works, but is bulky, and as I learned could be a failure point if you don’t do the maintenance.
Sorry for the drift @GJM