4-ounce, 100% polyester double knit with PosiCharge technology; White is 4.3-ounce for increased coverage Self-fabric collar Tag-free label 3-button placket with dyed-to-match buttons Open hem sleeves CARE INSTRUCTIONS Machine Wash Cold, With Like Colors, Do Not Bleach, Do Not Use Fabric Softener, Tumble Dry Low, Remove Promptly, Cool Iron if Needed, Do Not Dry Clean