The Smartwool Hiking Liner Crew can be worn as an ultra light sock on warm hikes or as a liner in cold weather. The ribbed cuff keeps it from sliding into your hiking boots or bunching at the bottom of your outer-layer sock. A flat-knit toe seam won't bother your toes while breaking trail. Smartwool designed the Hiking Liner Crew Socks to prevent blistering as well as odor.