Semperfli Nano Silk Pro 20D Thread

Semperfli's Nano Silk Pro 20D Thread is the ultimate choice for tiers who demand strength without sacrificing a low profile with minimal bulk. At just 20 denier (24/0), this ultra-fine, gel-spun polyethylene thread lays completely flat—spinning it will make it more round—making it ideal for precision work where bulk is the Achilles' heel. Despite its thin diameter, it boasts an impressive breaking strength of 750 grams, enough to firmly lock down materials on even the tiniest of hooks. Whether you’re tying midges, tricos, or just need your thread to be as thin as possible, Nano Silk Pro 20D delivers pro-level control and performance you can trust.

Uses

Nano Silk Pro 20D really shines on flies ranging from size 18 down to size 32 and below, especially when tying detailed patterns like tricos, RS2s, or tiny CDC emergers. Because it can be split easily, it's also a go-to for dubbing loops on delicate thoraxes or soft hackle collars. The ultra-flat nature of the thread helps maintain proportion and avoids creating unwanted thread build-up, making it perfect for tight, clean heads and bodies where every wrap counts.

Comparisons

Compared to a thread like Danville Spiderweb, which is also a great choice for micro patterns, Nano Silk Pro 20D offers a more durable, stretch-resistant profile and a much higher breaking strength. While Spiderweb is known for its invisibility, Nano Silk’s GSP construction keeps the thread from fraying and gives it a smoother laydown with better tension control. For tiers who value both delicacy and structural integrity, Nano Silk Pro delivers more versatility without compromising finesse, but both are reliable options anytime you're looking for minimal bulk or are tying small patterns.