The Progress MB TDR men’s T-shirt with long sleeves is made from a mix of functional materials from natural fibres with properties superior to those of synthetic fibres. The outer layer is made of merino wool and the inner layer is made of bamboo fibre. The T-shirt is soft to the touch. Merino and bamboo fibres promote better thermal regulation by providing cooling and warming effect depending on your body’s current temperature. Merino also prevents bad odours and keeps you warm even when wet. This makes this model perfect for a wide range of outdoor activities of all levels of intensity, from hiking to mountaineering.