Built for demanding fly tying, this heavy-duty thread is ideal for big saltwater patterns, bass bugs, and other applications where maximum strength and durability matter. Made from polyester (the same material used in classic 6/0 & 8/0), it won’t dull fly-tying scissors and offers reliable handling at the vise. 400 denier for powerful wraps on large flies Tested breaking strength up to 100 oz. Approximately 4x stronger and 4x thicker than typical 6/0 thread Excellent for spinning deer hair Untwists quickly and easily for flat-thread applications Lies flat without the slickness of Kevlar 80 yd. spool If you’re tying big, tough flies and need a strong thread that handles cleanly, lays flat, and cinches down securely, this is a dependable choice for saltwater, bass, and oversized fly patterns.