REI Midweight MTS Bottoms
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Soft and comfortable, the MTS midweight long underwear bottoms from REI are lightly brushed on the inside with a spun polyester on the outside for an excellent warmth-to-weight ratio. MTS(R) (Moisture Transport System) fabric wicks away moisture and dries quickly. Lycra(R) spandex helps garment stretch. Fabric provides UPF 50+ protection from harmful solar rays. Flat seams eliminate bulk; rib-knit ankle cuffs help seal out cold.