We designed this lightweight, packable micropuff to be worn as insulation under your shell on the mountain. But you’ll don the Calypso Jacket off the hill, too. It fits sleek and slim and since it doesn’t have a hood, it’s perfect for layering. (Think of it like the cheese in your layering sandwich.) Its PrimaLoft Eco insulation is made from 60 percent post-consumer recycled goods to keep those pesky water bottles out of landfills. It’s packed with technical features, too: Durable Water Repellent and waterproof zippers to keep you dry and calculated stitch lines for movement.