Insulated base layer providing a high level of thermal performance without bulk.Our warmest Rho base layer pant combines Fortius Air 20 nylon and Coreloft Stretch synthetic insulation with Torrent microfleece panels at the lower leg, waistband, and crotch gusset to deliver a high level of thermal performance without bulk. The next-to-skin fit layers easily, and articulated patterning combines with stretch for freedom on climbs, uptracks, and descents. What's been updated: Updated with two exterior drop pockets and stretch Coreloft™ insulation for improved freedom of movement, revised seam placement at the knee and inner calf to reduce chafing, and a next-to-skin fit for comfort under outer layers.