Synthetic base layers are designed to be worn next to the skin, providing user comfort by maintaining body temperature and controlling moisture. The fabrics used are highly wicking (they will spread moisture out over a large area), fast drying and breathable. It is therefore essential to maintain these properties when caring for base layers. Synthetic base layers are fantastic for regulating your temperature and controlling body moisture, but over time a build up of bacteria and body oils can lead to them smelling. To keep synthetic base layers functioning properly, care must be taken when washing. Using conventional household detergents or fabric conditioners can impair wicking properties by causing the fabric to retain moisture. This leads to reduced wicking capabilities and slow drying of the fabric. Additionally, odors will not be adequately removed, instead they are masked by perfumes which will fail quickly, leaving you with smelly base layers! All active people should use base layers to effectively manage body moisture and regulate temperature. Hill walkers, runners, cyclists, and mountaineers are among those who use base layers to maintain their comfort while active. Once your base layer has been used a few times and is starting to smell, wash it with Nikwax BaseWash to deodorize, freshen, soften, and enhance drying and cooling. Always apply this product to used synthetic base layers, socks, sports apparel and travel clothing to keep them in perfect condition. Shake well before use. Follow care label instructions. Do not use fabric conditioner. Do not use on waterproof clothing. Place item(s) in washing machine. Use 2fl oz/50ml of Nikwax BaseWash for front loading washing machines. * Wash according to care label.