Improving on our lightest technical running fabrics, microventilated SwiftTex polyester stretches, wicks sweat and dries fast to keep you cool on the trail Underarm gussets and side vents make moving easy Flat seams throughout are soft and nonchafing Reflective trim front and back Machine wash warm; do not bleach; line dry REI is Climate Neutral Certified; as we work to actively reduce our footprint, we measure annual carbon emissions and purchase an equivalent amount of verified carbon credits Contains materials that meet the bluesign® criteria Made in a Fair Trade Certified™ factory