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Why mess with separate base layers? The REI Midweight Polartec(R) Power Dry(R) Allstar Suit delivers one-piece warmth to defy the chill and keep you skiing or snowboarding to the last chair. Polartec Power Dry utilizes two different yarns on either side of the fabric to enhance comfort: interior yarn wicks moisture, and exterior yarn dries quickly. Combination of the two yarns helps keep you dry during highly aerobic activities because it moves moisture away from skin faster than single-component fabrics such as cotton. Waistband zipper with a functional fly is easy to undo when nature calls. Flatseam construction is soft and non-chafing next to skin. Fabric offers a UPF rating of 20 to protect against harmful UV light. The men's REI Midweight Polartec Power Dry Allstar Suits feature a next-to-skin fit that hugs the body.