Filson's heavyweight 24-oz. Mackinaw Wool provides natural insulation, breathability, and superior water repellency. It comes from a small herd of hardy sheep in the northwestern United States and Canada. Filson's wool will absorb as much as 30% of its own weight in moisture without becoming damp, allowing it to retain warmth even when wet. The fibers can even be bent and flexed 20,000 times without breaking. There is no finer wool than Filson’s 100% virgin Mackinaw Wool.