4.3 oz 100% polyester double knit Jacquard fabric. Opti-Dri technology transfers moisture away from the body to keep you cool and dry. UV Repel technology keeps skin safe from the sun's harmful rays. UPF 15+. Self fabric collar. 5-button placket with Callaway embossed buttons. Rounded bottom with double needle stitching and side vents. Heat seal label provides tag-free comfort. Contrast heat seal Callaway logo on back neck.