Hollow fiber construction provides superior thermal insulation. Thermolock™ draft tube prevents heat loss through the zipper. ZipPlow™ zippers protect fingers by allowing a snag-free opening and closing of the sleeping bag. The Roll Control™ system keeps the bag straight when rolling up for an easy pack-down in the included sack. Machine washable for easy cleaning. Comfort Rating: 3°C. Comfort cuff surrounds your face with softness. Cosy oversized sloop neck and rectangular design. Brushed polyester cover and liner for extra comfort.