The Smartwool Active Boxer Brief blends ZQ-certified Merino wool with recycled polyester to manage moisture, regulate temperature, and control odor from morning to night. A double front panel adds real support, and flatlock seam construction keeps the fit smooth against the skin to cut down on chafing. A wide elastic waistband and slim fit round out a brief built to disappear under whatever the day holds. What Our Gearhead(R) Experts Are Saying:"I wore these through a full day of travel and a hike on the other end, and never once thought about them until I changed at night."