Infrared rays are a type of thermal radiation, but they are studied in four sections when evaluated according to the wavelength parameter. In the infrared spectrum, the wavelength between 6µm - 14µm is defined as the far infrared (FIR) region. The human body is also an important source of FIR

POLY-thermo ® yarns are yarns used in winter sports and outdoor applications that help increase body temperature by providing thermal insulation. The yarns offer excellent thermal absorpt, on and rapid warming up to +13 °C for inner-outer wear and technical purposes.