The Men's Arc'teryx Beta Insulated Jacket is a waterproof and insulated jacket for alpine exploring. The mountains are vast, and the weather can change at the drop of a hat. Protect yourself against the elements during every hike into the mountains with durable 40D GORE-TEX fabric for waterproof, breathable protection. The lightweight Coreloft Continuous insulation provides warmth against the cold temperatures. As the sun rises and falls and comes and goes through the clouds, pit zips allow for quick ventilation during high-exertion activity.