Raprance 200D Fly Tying Thread Fly Fishing Material for Fly Fishing Wet Dry Nymph Tieing Supplies, Silk Sewing Thread - 100 Yards (Pack of 2) is a high quality thread that is perfect for fly fishing. It is made of 100% high-grade polyester and has a diameter of 0.20mm. The thread is thin and strong, making it easy to tie flies with, and it has a high resistance to water and UV rays. The thread is also very smooth, making it easy to work with and reducing friction when tying flies. The thread is also colorfast, meaning that it will not fade or lose its color over time. The thread is also very durable, meaning that it will last for a long time and will not break easily. The thread is also very flexible, meaning that it can be used for a wide range of fly fishing techniques. The thread is also very easy to store, and it will not take up much space. Overall, Raprance 200D Fly Tying Thread Fly Fishing Material for Fly Fishing Wet Dry Nymph Tieing Supplies, Silk Sewing Thread - 100 Yards (Pack of 2) is a high quality thread that is perfect for fly fishing. It is made of high-grade polyester, is thin and strong, has a high resistance to water and UV rays, is smooth, is colorfast, is durable, is flexible, and is easy to store.