P/D - the "frog" is simply another way to carry the knife/sheath. Old-time Mountain Men and such often had knife sheaths with just a stud sticking out of the leather, which would support the knife and prevent it from falling off his belt or capote sash/belt. The "frog" goes around the sheath and catches the stud with the notch, and provides a more secure carry than just tucking the knife in a belt, as it also has a belt loop. I hope this explanation makes sense! <img src="/ubbthreads/images/graemlins/crossfingers.gif" alt="" />