100% McAlister Duration wool. Heavy weight wool that is not bulky or itchy. Strong wool fibers will provide years of comfort and reliability. Designed to be worn as an outer layer, under waders when a coat is not wanted or needed. Tailored with a slim cut so as not to add bulk when worn under a jacket. Combined with 6.5 ounce wax canvas on the shoulders and arms provides added protection from briars and thorns while reassuring the water resistance.  Quarter zip turtleneck. SIZES: S, M, L, XL, XXL, XXXL COLOR: Oak, Olive, Advantage® MAX-4 HD™ WHAT MAKES WOOL SO SPECIAL Wool fibers consist of an inner core of protein, which is covered by overlapping scales. The protein core will absorb up to 30% of its weight in moisture without becoming damp or clammy. The scales are hard, reducing wear and tear on the fibers, at the same time preventing water penetration. Wool also contains lanolin, a natural water-repellent grease. The wool or fleece on a sheep protects the animal by first turning away rain and water. The fibers are strong and elastic, and are usually wavy, or crimped.The crimp of the wool produces insulating air spaces within the fleece, which reduces the flow of body heat. The air near the skin is kept dry as the core protein traps moisture from this air, and repels it toward the outside of the fleece. The elasticity and strength of the fibers allow movement of the fleece without losing the air spaces or breaking the fibers. The scales, aside from repelling water, also naturally repels dirt. Since all wool fibers outer ends point in the same outer direction, movement of the fleece tends to push dirt to the outside.