[DaMadman]

Really nice way to use one of those is to stop short when throwing a punch.

With your hand through the strap and formed in a fist, if you throw a punch in the area of the mid face and stop just short of making contact that spring allows the lead to travel forward thus popping the culprit square in the forehead and most of the time to their knees.

Grandad's brother was a D.C. cop and he used them like that.