Ultra Thread 140D by UTC
Ultra Thread 140D is ideal for most fly sizes, particularly sizes 2 to 16. Its vibrant sheen and strong color retention make it an excellent substitute for floss on small flies. Available in 100 yards per spool.
Engineered for Fly Tying Performance
Ultra Thread is specifically designed for fly tying, not a generic off-the-shelf product. Key features include:
- Nylon is used instead of polyester because it stretches and grips materials better, improving tying performance.
- Provides consistent strength and durability during the tying process.
- Retains color well, ensuring visibility and accuracy in fly construction.
| Specification | Value |
|---|---|
| Thread Type | Nylon |
| Denier | 140D |
| Length per Spool | 100 yards |
| Best For | Fly sizes 2–16 |
FAQ
What makes Ultra Thread 140D different from other fly tying threads?
Ultra Thread 140D is specifically engineered for fly tying, using nylon for better stretch and grip. It is not an off-the-shelf product but designed from the ground up to enhance tying performance and color retention.
Is Ultra Thread 140D suitable for small flies?
Yes, its vibrant sheen and color retention make it a good substitute for floss on small flies.
What is the length of each spool?
Each spool contains 100 yards of thread.

Sean Simpson –
I’ve used Ultra Thread 140D for several months on small and medium flies. The color stays bright and the thread holds well during tying. It’s easier to work with than regular floss, especially when making fine patterns.
Peter Mathis –
The nylon construction gives it a good grip on the hook. I noticed less slippage when tying compared to polyester threads. It’s a reliable choice for consistent results.
Hannah Springer –
I switched from floss to Ultra Thread 140D and found it much more manageable. The sheen helps me see the fly structure better, and it doesn’t fray easily during tying.