The Smartwool PhD Outdoor Light Crew Socks are highly coveted by women who enjoy trail running. These socks are crafted with a blend of merino wool, nylon, and elastane, offering a perfect combination of comfort, durability, and stretch. The light cushioning provides impact absorption and support without adding bulk. The merino wool fibers naturally regulate temperature, keeping your feet warm in cold weather and cool in hot weather. These socks also feature a 4 Degree Elite Fit System for a secure and snug fit. Whether you're tackling steep inclines or navigating rocky trails, the Smartwool PhD Outdoor Light Crew Socks will keep your feet comfortable and blister-free.