Proven across a range of alpine missions and backcountry adventures, the Cerium packs small, weighs little, and delivers big warmth. The design – refined for optimal fit and efficiency – utilizes more sustainable materials while delivering the same outstanding warmth-to-weight ratio. Responsibly-sourced 850 fill down – with Coreloft synthetic utilized in areas prone to moisture – provides premium insulation. The recycled 15D Arato nylon outer is light and durable, the bio-derived liner reduces petroleum use, and the streamlined design is articulated for freedom of movement.