Warm, versatile Polartec® Power Stretch® Pro base layer for cold conditions. *The Kyanite Baselayer Bottom was previously the Rho Heavyweight Bottom. The Kyanite Baselayer is made for cold days and mixed output. On the move, the Polartec® Power Stretch® Pro stretches for outstanding freedom of movement. During rest phases – or when it gets really cold – the fleece’s soft brushed interior traps heat to keep you warm. The fleece’s durable nylon outer has a smooth face for comfort under layers, and a zippered thigh pocket secures small essentials. Updated with a new fabric made with recycled content. Full Product Features Technical Features - Moisture-wicking - Durable - Versatile - Warm and comfortable Construction - Polartec® Power Stretch® Pro fleece combines a highly durable nylon face with a soft, comfortable, brushed polyester interior made with recycled content Design & Fit - Trim fit keeps warmth close to the body - Trim fit makes it an ideal layering piece Logos & Label Configuration - Subtle Arc'teryx logo Patterning - Articulated patterning for unrestricted mobility Pocket Configuration - Laminated zippered thigh pocket sized for smartphones Sustainability - Contains materials that meet the bluesign® criteria - Biocidal Disclosure - This model was treated with an anti-odour biocidal product (Active Ingredient: Silver Nitrate) - PFAS (Per- and polyfluoroalkyl substances) Compliant Materials - Origin of fabric: UNITED STATES - Origin of dying: UNITED STATES - May release plastic microfibres into the environment when washing