100% Polyester. Fabric: Stretch. Design: Plain. Neckline: Crew Neck. Sleeve-Type: Short-Sleeved. Hem: Twin Needle Stitch. Cuff: Twin Needle Stitch. Fabric Technology: Lightweight, Moisture Wicking, UV Protection. Tearaway Label. 135gsm. Sustainability: Amfori, BSCI. Sun Rating: UPF 40+. 5-6 Years: 24 in. 12-13 Years: 32 in. 3-4 Years: 22 in. 7-8 Years: 26 in. 9-11 Years: 29 in.