The Fjellrapp Half Zip merino undergarment by Bergans is made of pure merino wool. This makes it incredibly soft and warm. Its high standing collar also keeps the neck well protected. If it does get warmer, then the short front zipper can be used to open up the collar and allow cool air to flow through to your body. Warm, soft and cozy: The Fjellrapp Half Zip merino undergarment. ;"