Polar Fiber is a unique type of craft fur that?s excellent for tying baitfish and crustacean patterns. It?s slightly longer than other craft furs (over 2 1/2??) and has excellent movement under water thanks to its soft, thin fibers. It doesn't absorb water, which makes it much easier to cast big flies. Plus, Polar Fiber has a quick sink rate due to the fiber's small diameter.