Sleepcell Ultravent Ultra Coolvent Sleeping Bag, 30-70 Degree, 3.5 Lb., 38" X 85" Removable air pillow with a comfort foam pillow liner and soft to-the-touch brushed polyester cover New hi-top collar for additional comfort on cool nights. Poly 300d PU coated base for added protection Poly diamond ripstop shell, a durable, easy care outer fabric. Soft moisture wicking liner keeps you snug, warm and comfortable Ultravent control the inner temperature with the glide of a zip European Standards EN 13537, hold temperature 30 ~ 70 degree One Hole Litron polyester fiber locked away between two layers for added warmth. Easy to pack expandable compression bag