When you need the very strongest thread go with kevlar. We like it for tying glo bugs or spinning sculpin wool head flies. 50 yards per spool.
Thread - W. W. Doak and Sons Ltd. Fly Fishing Tackle
Wapsi Ultra GSP Thread is the strongest thread on the planet. Boasting steel-like strength for its weight, this thread really lets you put the pressure on! Gel spun polyethylete is supple, ties flat. 75 denier is the ideal choice for all trout flies. It is small enough to tie tiny dry flies and strong enough for the largest trout streamers. It is an excellent all purpose fly tying thread. GSP 100 has all around versatility for fresh and saltwater flies.
UTC Ultra GSP Thread 200 Denier / Red
Thread/Tinsel/Wire — Big Y Fly Co
Kevlar Thread - Wilkinson Fly Fishing LLC
Darke's Naknek Sockeye Smolt #2 - Fry & Baitfish Flies - Alaska
DescriptionVeevus Kevlar Thread brings Veevus quality along with Kevlar Thread strength. Be careful with this Kevalar its so strong you can cut your
Veevus Kevlar
Abel Skull and Crossbones picture thread
Kevlar Thread 200 Mossy Creek Fly Fishing
Thread, Tinsel & Wire - Fly Tying - Alaska Fly Fishing Goods
Used to tie bulletproof flies. Kevlar thread is one of the strongest available. Natural yellow color, 50yd. spool, 200 denier.
Kevlar Thread
Kevlar Thread - Thread - Alaska Fly Fishing Goods
Fly Tying Thread, Construction, & Materials - Fly Fisherman
Thread, Tinsel & Wire - Fly Tying - Alaska Fly Fishing Goods