5 oz, 100% POLYESTER JERSEY KNIT FABRICOpti-Dri technology transfers moisture away from the body to keep you cool and dryUV Repel technology keeps skin safe from the sun's harmful rays UPF 15 3-button placket, self-fabric collar, open sleeveDouble needle hemmed bottom with side ventsHeat seal label provides tag-free comfortTonal embroidered Callaway logo on right sleeve