SmartWool NTS 250 Funnel Zip Running Top Material - 100% Merino Wool UPF 50+ - UV protection which keeps you safe from harmful rays. Smart Seaming - Seams are designed to wrap to the contours of your body for an enhanced fit and improved mobility. Flatlock Seams - Eliminates chafing to keep you completely comfortable. Heat Transfer Logo - At left sleeve cuff.