"The Merino 260 Quantum Zip Jacket uses 100% merino wool at a 260 warmth rating to regulate temperature and resist odor through repeated wear. Its fitted, hoodless silhouette slides cleanly under a shell or into a pack without the added bulk a hood brings, making it a straightforward mid-layer for backpacking and cold-weather travel alike. Backpack-compatible zippered hand pockets and a hidden chest pocket keep essentials secure, while thumb loops seal out cold air at the wrists. What Our Gearhead® Experts Are Saying:""I packed this instead of my usual fleece for a five-day trip and never missed the extra bulk. It compressed down small in my bag and still kept me warm layered under a shell on the coldest mornings."""