When it comes to chilly winter hikes, our clever Ventrix™ Light Hybrid Sweater is your secret weapon. It may look like an ordinary sweater, but it's made with advanced Ventrix™ synthetic insulation in the body. This works by keeping you warm when you set out, using perforations on the back to prevent you from overheating as your body works harder. Its lightweight, highly air-permeable fabric means it's breathable at the same time as being warm, regulating your temperature to keep you comfortable right to the end of the trail.