Mid-Layers can be worn over a single layer to keep you warm enough whilst hiking, but not so warm that you sweat profusely. Mid-layers are traditionally used as a layer to go on hiking. They are also used in colder temperatures when you need more than a single layer on your upper body. These are often called “active mid-layers” as they allow moisture to escape better than rain jackets or puffy jackets.Explore Bogner Stockist UK for a lot of good collections and find what works for you and your requirements. be sure the selected apparel should be fitted without being snug to trap warmth and be easy to move in.