STAY-COOL WICKING ULTRA BREATHABLE FLATLOCK SEAMS FOR COMFORT AND REFLECTIVE DETAILS. 4.4-OUNCE 100% POLY JERSEY WITH STAY-COOL WICKING TECHNOLOGY. FEATURES OGIO® ENDURANCE HEAT TRANSFER LABEL FOR TAG-FREE COMFORT, RAGLAN SLEEVES WITH CONTRAST FLATLOCK SEAMS, CONTRAST FLATLOCK SIDE SEAMS, REFLECTIVE O HEAT TRANSFER ON LEFT SLEEVE, REFLECTIVE STACKED O HEAT TRANSFERS AT CENTER BACK, AND REFLECTIVE O ENDURANCE HEAT TRANSFER AT FRONT LEFT HEM.