Universal 30% Merino and 70% Polypropylene T-shirt. Flat seams that do not hurt; antibacterial. The T-shirt is made of a functional rib knit and its inner side features a finely combed blend of Merino wool and polypropylene. The polypropylene provides for the best possible moisture wicking away from the body surface towards the outer layers of clothing. The Merino wool enhances the thermal insulation properties.