The Summit 250 Extra Large Sleeping Bag is perfect for outdoor use during cold weather. Designed with ripstop polyester fabric, in a mummy shape to lock in warmth, with hollow fibre insulation and an extreme temperature of -20°C. 3/4 Season - Cold nights early Winter Two Way Zip - A two-way zip is useful for easy opening when ventilation is required. Zips can be full length or just half way. Hood - Much of your body heat is lost through your head, a shaped hood will help keep in heat. A draw cord closure allows you to pull the hood tight against your face for added warmth. Inner Pockets - An inner pocket to keep your valuables safe and close to you while you sleep Mummy Shape - Mummy shaped bags follow your body shape, giving you a cosier night's sleep Double It - You can zip two of.