Stretchy, breathable, and compression-resistant, the Polar Stretch Mid-Layer Boot Liner is made from anti-microbial fleece. Includes Polartec Power StretchA(R) technology. Features Includes moisture management technology that acts as the second stage in moisture movement away from the skin Incorporates quick drying characteristics for rapid evaporation, keeping you dry and comfortable Includes anti-microbial properties that inhibit bacterial growth, keep the fabric fresh and provide odor control Flatseam stitching throughout Packaged in a PLA Compostable/Recyclable Bag