The Active Spine tee is a fantastic choice for running. Its material transfers moisture, and the Active Spine structure in the upper back helps keep your posture in check. - Slim fit - Posture enhancing Active Spine structure in the upper back - Light series product: the manufacturer recommends this shirt for 15 - 25 degrees in low exertion situations, and -25 to +10 in high exertion sports Organic body mapping: A new generation technology that allows the garment to function according to your physical needs. Some body parts move more than others, creating warmth at different intensities. Some parts are warmer, while others are colder, calling for more insulation. - Protects you in varying weather conditions - Good insulation - Efficient moisture transfer