Mizuno Breath Thermo Women's Long Sleeve Running Top - X Small - Purple Breath Thermo Yarn - Captures escaping body heat and through a patented physical reaction in the yarn, generates heat  warming the body. Dynamotion Fit Patterning - Provides a better anatomical fit of garment, offering freedom of movement. Strategic Ventilation - For superior thermoregulation. Reflective Logo and Accents - Located on the front and back, ensuring you remain visible in low light conditions.