5.3 OZ. 95% polyester. 5% elastane French terry. 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. Stretch fabric moves with you to increase your range of motion. 1/4-zip with Callaway logo rubber zipper pull. Contrast binding detail at chest and cuffs.