REI Silk Bottoms
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This base layer is smooth, yet robust and warm enough to wear under a pair of jeans on a cold day. Lightweight, breathable, pure silk jersey is enhanced with a wicking treatment to help keep you dry and warm. Wide, self-fabric elastic waist with fly front, seamless sides and rib-knit cuffs provide a comfortable fit throughout. Machine wash in cold water on gentle cycle, or hand wash.