Product Details UTC Ultra Thread 140 & 210 Denier delivers the strength and control fly tiers need, with a smooth, lightly waxed nylon build that lays flat for precise wraps. UTC 140 works well for trout flies in sizes 616, while UTC 210 handles deer hair, salmon, steelhead, and saltwater patterns from sizes 1/012. Both options offer solid breaking strength to help anglers tie durable flies with Read More UTC Ultra Thread 140 & 210 Denier delivers the strength and control fly tiers need, with a smooth, lightly waxed nylon build that lays flat for precise wraps. UTC 140 works well for trout flies in sizes 616, while UTC 210 handles deer hair, salmon, steelhead, and saltwater patterns from sizes 1/012. Both options offer solid breaking strength to help anglers tie durable flies with confidence. UTC 140 General-purpose thread for trout flies Best for flies sizes 6-14 2 lbs. breaking strength UTC 210 Ideal for deer hair, salmon, steelhead, and saltwater flies Best for flies sizes 1/0-8 3 lbs. breaking strength Each spool contains 100 yards of lightly waxed nylon thread Made in the USA Prop 65 Warning SEE LESS