"What Our Gearhead® Experts Are Saying:""This fleece is my go-to midlayer when the temperature drops. The Polartec® Thermal Pro® fabric is incredibly warm for how lightweight it is, and I love how fast it dries after a long day on the mountain. The flat seams keep things comfortable under a pack, and the zippered pockets are perfect for stashing essentials. Whether layering up for the slopes or wearing it on its own, this jacket is a winter essential.""From crisp morning hikes to après-ski lounging, the Mammut Arctic IV ML Jacket delivers the warmth and comfort we need for cold-weather adventures. Made with high-performance Polartec® Thermal Pro® fleece, this midlayer offers an excellent warmth-to-weight ratio while remaining breathable and fast-drying. Whether we’re layering it under a shell or wearing it solo, the soft, lofted structure traps heat while resisting pilling for long-term durability. Designed for performance, this fleece features flatlock seams to prevent chafing under a pack, zippered pockets for secure storage, and elastic cuffs and hem for a snug fit. Whether we’re hitting the slopes, hiking in brisk conditions, or enjoying a relaxed day outdoors, the Arctic IV ML Jacket is a dependable go-to for all things winter."

Key Specifications