The intelligent X-BIONIC® INVENT® LT SINGLET for men counteracts overheating risks. It cools when you sweat and warms you when you are cold. Wear it for running, cycling, trekking, and any other athletic activity. Feel more powerful and comfortably regulated. The integrated 3D Bionic Sphere® System cools when you sweat and warms you when you are cold. Sleeveless, pleasantly close-fitting, and with an advantageous thin structure, this singlet can be worn under your sports clothing without adding bulk. All you feel is exactly the cooling effect you desire on warm days.