POLARIS HAIR is the finest, non-water absorbing fly tying winging material I have ever seen. The manufacturer tells me that it is .0005 inches thick! It has a shine and stiffness that I believe is perfect for larger flies - sized 10 and up. I use the CURLY to build bulk in addition to N.E.W. in flies sized 2/0 and above. Or use with any other flash materials. This version has a very tiny wave to the fibers. Even as thin as it is, this special wave helps to keep it straight preventing it from getting wrapped around your hook in casting, along with supporting finer flash materials. Packs are a full 11.5 inches long for those who tie the larger flies and lures.