UNI-Thread is comprised of strong, continuous denier polyester filaments. The properties of this thread allow it lay flat on the hook or can be twisted tight by spinning the tying bobbin. UNI-Thread is extremely strong for its diameter. This waxed thread is recommended for small fly work by the FishUSA staff. Made of continuous polyester filaments slightly bonded The filaments are not twisted Tie virtually flat on the hook 3/0 should be used for flies larger than size #12 Size Denier 3/0 220 6/0 136 8/0 72