Description: Ultra Thread is a strong, flat, smooth, lightly waxed, slow building nylon thread. UTC 140 is great general purpose thread for trout and other flies in the 6 to 16 size. The breaking strength of this thread is about two pounds. This tread will serve the beginning fly tier well, as it is not too bulky and it strength prevents breaking the thread until proper techniques are learned. This thread comes on spools containing 100 yards of material.