The Pace Air Tee is built for high-pulse activities like running, fast-paced hiking, and mountain biking in warm or humid conditions. It uses Rerun Jersey, an ultralight 115 g/m² fabric made from 100% recycled polyester that stretches freely, resists snagging, and dries quickly to maintain comfort over extended efforts. The slim fit moves with the body without restriction, and flat seams are positioned to minimize chafing during sustained activity.