Upavon Nano Worm Chenille is a micro-diameter flexible worm material — the smallest profile in the worm chenille range, built for tying San Juan Worm and squirmy-style patterns on smaller hooks where standard worm materials add too much bulk and obscure the hook gap. The fine diameter sits proportionate on size 14–18 hooks, the flexibility gives it the natural undulation in current that triggers takes on pressured tailwater trout, and the vivid professionally dyed colors hold without fading after repeated use.