Sport-Tek® PosiCharge® Tough Tee?. ST320. Worthy of its tough name, this snag-resistant tee is durable, soft and smooth. Great moisture wicking combined with bleed-resistant PosiCharge technology means it will perform and endure time after time. 4.7-ounce, 100% polyester jersey with PosiCharge technology Removable tag for comfort and relabeling Set-in sleeves