Description of The North Face Nuptse Bootie II Instead of tromping around in your boot liners, or in the boots you’ve been wearing for the past 18 hours on your ascent, give your feet a reprieve in the Nuptse Bootie II. Quite possibly the warmest and most comfortable slip-ons on Earth, these booties are suitable for everyday wear, inside and out, thanks to water-resistant, down-insulated uppers and Ice Pick™ temperature-sensitive rubber pods for traction on the soles. Features: [Bottom] Cushioned compression-molded EVA midsole [Upper] Water-resistant, durable ripstop nylon upper 700 fill synthetic down insulation Abrasion-resistant rand Collar drawcord lace with barrel lock Ice Pick™ temperature-sensitive rubber pods for increased traction Internal ankle-securing elastic Northotic™ footbed