The suggestion of these being actually used...you could take this two ways but, we had one for our FN C2 that carried four(issue five). That wasn't enough mags or ammo and was a horrible thing to wear. This would just be worse. I expect they were just a flash in the pan like the shovel with a hole in it for WW1. Lots produced but never actually accepted or brought into service. That's why so few have seen them.