Yes, "AK" stands for Ass-Kickin'. And these legs are just that. Say goodbye to knotting pheasant tail for good. Why spend all that time for a result that is not realistic or flexible. AK Hopper Legs come in 4 sizes to fit every possible fly you can design. They are made from the same "lighter-than-water" material as our Wiggle Stone Bodies, and they move and flex with every tiny disturbance on the water.