5.8 oz 95% polyester, 5% spandex jersey knit fabric. Opti-Dri technology transfers moisture away from the body to keep you cool and dry. UV Block technology keeps skin safe from the sun's harmful rays. UPF 50+Self fabric collar. 3-button placket with Callaway embossed buttons. Double needle hemmed bottom with side vents. Heat seal label provides tag-free comfort Contrast heat seal Callaway logo on right sleeve.