The SmartWool NTS Microweight 150 Baselayer Long Sleeve Running Top provides great thermoregulation and moisture-management qualities, keeping you cool and comfortable whilst exercising. Merino wool is a natural fabric, and is great for regulating your body temperature and heart rate due to its natural breathability and moisture-management properties. This happens easily when wearing the natural wool in comparison to a synthetic fibre. The SmartWool NTS Microweight 150 Baselayer Long Sleeve Running Top wicks sweat away from the body to keep you dry, and also traps air in its fibres to keep you warm. The top is lightweight and slim-fitting, creating warmth without adding bulk for a more comfortable fit. Sculpted side panels create a smoother fit, reducing the chafing that can occur whilst exercising.