Functional underpants long, special Outlast® viscose fiber, cooling or warming depending on body activity. Outlast® - originally developed for Nasa. Trevira®Bioactive has a permanent antibacterial effect and prevents the formation of odors. First-class wearing comfort due to flat seams. Perfect clothing physiological properties ensure an ideal microclimate. Ideal temperature balance between warm and cold. Therefore excellent use for activities with temperature fluctuations.