What Our Gearhead® Experts Are Saying:"I always reach for this jacket when I need reliable warmth without bulk. The PrimaLoft® Silver RISE insulation keeps me warm even in damp conditions, and the stretch fleece side panels give me full range of motion while climbing or hiking. It layers easily under a shell, and the under-helmet hood is a game-changer for added coverage in cold alpine starts. Plus, it stuffs into its own pocket, so I never hesitate to bring it along."When we’re chasing summits or setting out on crisp morning hikes, the Cirrus Flex Insulated Hooded Jacket from Rab is our go-to for lightweight warmth. Its PrimaLoft® Silver RISE insulation traps heat efficiently, even in damp conditions, keeping us comfortable through ever-changing mountain weather. Breathable Thermic™ stretch fleece side panels enhance mobility, making it easy to move freely on scrambles and technical climbs. Designed for versatility, this jacket works as a standalone layer on mild days or as an insulating midlayer in colder conditions. The Pertex® Quantum shell sheds light moisture, while the under-helmet hood construction provides extra coverage without sacrificing comfort. And when the sun finally breaks through, it packs down small into its own pocket—always ready for the next adventure.