Spark Sp0 Sleeping Bag Our Spark™ Series bags is what you reach for when you need a high performance sleeping bag but don’t want to be weighed down by one. The Spark™ Series spans everything from an ultralight liner to an expedition weight mid-winter bag. While the end usage is very different, they reflect a design ethos of matching weather conditions to the lightest bag possible.   Ultra-light and technical, our Spark™ Series bags are designed to keep you as warm as possible while minimising packed weight and size. Contoured mummy shape for efficient insulation Ideal for mid-summer fast hikes or adventure racing Doubles as a liner to significantly boost the warmth of a second bag