X-BIONIC VITALIZERWOMEN'S SINGLET LOW COMPRESSION SLEEVELESS TEETURN SWEAT INTO ENERGY. Sweat is too precious to throw it all away. Our skin needs moisture to cool itself down. When moisture evaporates from the skin an evaporative cooling process takes place that we use to maintain the optimal body temperature of 37°C. Traditional technical base layers absorb moisture in its entirety so then the body steps up its sweat production. The result: Water, minerals and salts are lost. The globally unique and patented 3D-BionicSphere® System leaves a light film of sweat on the skin. The body is effectively and naturally cooled as long as it’s sweating. If sweating stops, the insulation function kicks in and less energy is demanded for temperature regulation, which leaves more energy for your activity. DESCRIPTION: size: l/xl colour: white/blue sleeve: sleeveless materials: 98% polyamide/ 1% polypropylene/ 1% elastane condition: in oem packaging - sales rep's sample. never used. FEATURES: 3D-BionicShere System in the chest area - w/out giving the body the impression that it is getting cold, fresh air from the 3D-BionicSphere System cools down the body temp. The air is tempered inside the ducts, working like a sluice. Hot, moist air is disposed of using the dynamics of body warmth and then replaced with new fresh air. 3D-BionicSphere System on the back - Guarantees effective ventilation so moisture is quickly wicked and transported away. No sweat means insulating air pockets in the wavelike structure protect against cold. X-Impact Technology - Better performance due to graduated compression that reduces muscle oscillations, supports muscles and joints and optimises nutrient supply. please note: these shirts run quite small, but are made to stretch for a close fit.while 100% authentic, sales rep's samples do not qualify for the 2 year warranty.