STAY-COOL WICKING ULTRA-BREATHABLE FLATLOCK SEAMS FOR COMFORT REFLECTIVE DETAILS 4-ounce, 100% poly jersey body with stay-cool wicking technology 4.1-ounce, 100% poly mesh back panel Self-fabric collar Reflective O heat transfer at back neck Reflective stacked O heat transfers at lower back panels OGIO heat transfer label for tag-free comfort Reflective O heat transfer at front left hem