The Germans were very clever at making concealed weapons. One of the most ingenious was ostensibly a large,ornate ,belt-buckle, which concealed a number,up to nine I think ,of very small calibre ( 1.5 or 2 millimetre) spring-loaded gun barrels. The idea was that, when called upon to surrender, an Officer so equipped would slowly and deliberately position himself directly opposite his foe, and then undo his belt-buckle. As he did so, the battery of sub-calibre barrels would spring out and fire a volley of shots into the guts of his captor. Of course, we English were much less subtle, and anyway,a belt-buckle gun would not have been " sporting ", but we did issue a lot of agents with the "Welrod " gun. This was a very small,easily hidden one-shot pistol,with a very short ,smooth-bore barrel, chambered for the .45 ACP round.Cheaply made from pressed & stamped components,it had no range at all, but if held up close to the body of a victim,the damage could be devastating.They were designed as a last-ditch resort, & for opportunistic assassins who could get close enough to their targets.