These legs are a smaller square leg. Perfect for tying on nymphs, dries, or smaller streamers. When cut¬†short they¬†stick¬†out well and make a realistic profile. If you tie them in long they will flop around and create movement on streamers that bigger fish will find tantalizing.
Heck, you could even put them on a finesse jig for bass if you're in the conventional world.¬†