The Y MountainLine Light Insulated Air Vest is a high-tech, lightweight, and super comfortable outdoor vest. The unique combination of high-performance materials made from natural and synthetic fibers provides product features that you will appreciate both in the mountains and at home when planning your next adventure. The front, collar, and back are made from a lightweight Vivo Performance: Eco-quilted outer fabric that ensures the right balance between warmth and weight. The sides feature inserts made from a technically advanced technostretch knit fabric. This fabric is a blend of Cordura® and merino wool, which means it is warm, durable, breathable, and incredibly soft and flexible. Practical pocket in the chest area. A vest is perhaps one of the most useful pieces of outdoor clothing. So if your outdoor wardrobe doesn't already include a vest, now is the time to buy one!