We rely on down insulation for critical warmth when winter is at its harshest, so our Down Pilot's Vest, entrusted with the protection of our core, needed to feel like the armor it is. The rugged plain-weave polyester shell is tear and water-resistant, ensuring that nothing will keep the 600-fill down from working at maximum efficiency. And because down is so lightweight, our Down Pilot's Vest will disappear under any coat or jacket, and still hold its own when worn with just a base layer.