This was advice from some friends in USMC and was only a very temporary fix.Idea is plug the hole to keep the RED STUFF in until EVAC and proper medical treatment.They say "everyone" carries them "over there".Would I use one if a hospital or EMS was within an hour away,probably not.If one was way out and had nothing else,maybe.They are handy for other things(improvised water filters,fire tinder,etc.)as well as their intended purpose.

BOATMAN
John