The lightest bag in our Phoenix range, our Spark 150 is a lightweight and tough sleeping bag for two season camping. The Spark is filled with 150gsm spiral hollowfibre, a lightweight insulation that weighs only 1.1kg and can be packed into a stuff sack for easy travel. This is contained within a hard-wearing Ripstop shell that protects it from rips and scratches, and it has an extra-tough boot liner, so you can sleep with boots on without damaging the bag. For extreme temperatures, the Spark can be combined with the Flame, using a Simple hook and loop system, to create a 5 season sleeping bag.