RIO's Sili-Leg Stone features knotted legs that give the fly a remarkably lifelike appearance. We've taken those same legs and color combinations and created RIO's Knotty Hooker. The marabou portion serves as the abdomen of a stonefly nymph and provides movement. The chenille serves as the thorax of the stonefly nymph, which means the legs are positioned anatomically correctly. The tungsten bead serves as the head of the stonefly nymph, which is slightly smaller than its thorax. The jig hook allows you to fish at the bottom of the river with less concern of hanging up. But this fly shines under an indicator suspended just off the bottom.