Sport-Tek Posi-UV Pro Polo. ST520 Designed for game day or the work day, these high-performance polos offer a soft, matte hand and deliver exceptional UV protection, PosiCharge color-locking technology and moisture wicking., 4-ounce, 100% polyester interlock with PosiCharge technology, UPF rating of 50, Removable tag for comfort and relabeling, Self-fabric collar with collar stand, Taped neck, 3-button placket with dyed-to-match buttons, Set-in, open hem sleeves