Patagonia Encapsil Down Belay Jacket

The 18-ounce Patagonia Encapsil Down Belay Jacket boasts the best warmth-to-weight ratio of any jacket. The reason? Its down filling features a breakthrough silicone treatment that renders it water-repellent and increases its loft to a 1,000-fill rating. An independently baffled design eliminates cold spots while ensuring a precise fit. [$700; patagonia.com]