Ultra Thread's slim, round, multifilament build lays flat instead of stacking bulk, so matching denier to the hook is what matters most: 70D for size 14 and smaller, 140D for sizes 6–14, and 210D for streamers and big saltwater flies. Specifications Available In: 70, 140, and 210 denier, in a wide color range Spool Length: 100 yards Construction: Multifilament nylon, round cross-section, waxed with a slight twist Breaking Strength: 70D ~1 lb · 140D ~2 lb · 210D stronger still Best for: 70D on size 14 and smaller flies (comparable to Danville 6/0), 140D on sizes 6–14 (comparable to Danville Flymaster+ 140), and 210D on streamers, saltwater, and big predator patterns — all three handle split-thread techniques and dubbing loops. The waxed finish carries a slight twist that holds wraps secure and cooperates with split-thread techniques and dubbing loops rather than fighting them. 70D is comparable to Danville 6/0, and 140D to Danville Flymaster+ 140, for tyers matching a familiar diameter. The color range covers both subtle, natural patterns and flashier attractors without switching brands.
