Salewa Half-zip Tee Zebru Responsive is the ideal shirt for alpine mountaineering, and ski mountaineering. Optimal wicking warmth Baselayers are crucial during high-intensity cold weather missions. The Zebru Half Zip Tee is a performance baselayer constructed with super-fine merino wool (64%) for optimal wicking warmth, temperature regulation and next-to-skin comfort. Its uses thermal bodymapping and our proprietary Responsive technology to help you manage your body temperature. Far-infrared textile technology Named after Monte Zebru (3,735 m) in the Ortler Alps on the border of South Tirol and made in Italy, this performance baselayer is composed primarily of merino/poly fibres blended with Responsive polyamide yarns loaded with a unique mix of natural thermoreactive minerals. Responsive is a smart fabric that harnesses infrared energy by absorbing Far-infrared radiation (FIR) emitted by the body and gradually re-emitting it back to the muscle tissue. Research shows that it increases blood flow, enhances cellular performance and promotes greater oxygenation, so that you can perform better