What it is Hareline Flex Floss is a stretchy silicone leg and body material with a flat profile. On the hook it’s durable, rot resistant, and holds up well to teeth, and in the water it has a wiggly, alive motion because it flexes and rebounds. What to tie with it Use it for rubber legs and antennae by tying in short sections and letting the stretch give you that mobile kick. It also makes clean body wraps on midge pupae/buzzers and on nymphs, including slim Euro nymph and perdigon-style bodies, because the flat silicone lays smoothly when you wrap it. It’s also at home as legs on saltwater patterns where you want movement and toughness. Flies and the fish they're for San Juan Worm ties in naturally with this material’s stretch and wiggle, and it’s a go-to for trout in rivers and tailwaters when they’re keyed on worms. Pat’s Rubber Legs is a classic big nymph/stonefly look for trout, especially in freestone rivers and high-gradient runs where stoneflies are common. Gotcha-style flats flies use silicone legs for motion and durability, and they’re fished for bonefish (and often other flats species) in saltwater. How it compares Compared to Hareline Round Rubber Legs, Flex Floss is flat silicone rather than round rubber, and it offers better resistance to teeth. Compared to traditional rubber legs, the silicone is rot resistant.