REI Silk Long Underwear Bottoms

Extra layer for your legs when the temperature dips. Great sleeping wear as well.



Technical Details



Moisture Wicking


Quick Drying


Length Options

regular & long


  • Comfortable
  • Breathable
  • Quick-drying
  • Warm


  • May not provide enough warmth for extended time in the snow

Why We Like It

Comfortable, warm, and quick-drying: the trifecta of a perfect pair of long underwear. The REI Silk Underwear Bottoms are an affordable option for adding a layer when the weather turns cold. Smooth, soft fabric makes you almost forget they're on, while the just-right amount of warmth will make you glad you had them for those frigid trips up to the Matterhorn or to Mont Blanc.

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