MFC GSP Thread

When you need maximum strength with minimum bulk, reach for Montana Fly Company GSP Thread. Built from Gel Spun Polyethylene (GSP), this premium fly tying thread delivers extremely high breaking strength and zero stretch, giving you precise tension control for everything from micro patterns to heavy-duty streamers and predator flies.

Because GSP lays flat, you get clean wraps and sleek heads without building unnecessary bulk—especially important on smaller flies where every turn of thread matters. And when you’re cranking down on hair, foam, synthetics, or tough materials, MFC GSP gives you the confidence to pull tight and lock things in for durable, fish-ready flies.

MFC GSP threads are marker friendly for easy customization.

Why MFC GSP Thread Belongs on Your Bench

Ultra-High Strength

• Extremely high breaking strength for tight, secure, long-lasting flies
• Ideal for spinning deer hair, cinching down materials, and building durable patterns

Zero Stretch = Total Control

• GSP does not stretch, so your wraps stay exactly where you put them
• Delivers consistent pressure for clean, precise, repeatable tying

Flatter Wraps, Less Bulk

• Lays flat to reduce thread build-up on small flies and neat heads
• Great for sleek bodies, clean tie-ins, and crisp finishing work