STAY-COOL WICKING, FLATLOCK SEAMS FOR COMFORT, REFLECTIVE DETAILS. 4.3-ounce, 80/20 poly/cotton jersey with stay-cool wicking technology, OGIO heat transfer label for tag-free comfort, Reflective taping under flatlock stitching at the shoulders, Set-in sleeves, Reflective O heat transfer on left sleeve, Reflective OGIO Endurance vertical bar heat transfer on center back.