New Age Tying Thread | Global FlyFisher | GSP or Gel Spun Polyethylene fly tying thread was fairly unknown when Chris Helm wrote this article. His observations still stand.
Choosing the Right Fly Tying Thread
Gel Spun Vs Dacron Backing For Fly Reels — Saltwater Experience Fishing
GSP fly Tying Threads|GSP Threads
VEEVUS GSP THREAD Fly Tying Gel Spun Polyethylene Black White 30 50 100 150 200 | eBay
Silk threads and flosses, the classic fly tier tools | 54 Dean Street