You've got ultralight adventuring down to a science, right? Your pack and 90% of its contents is totally dialed in for fast and light on-trail travel in warm temps, but one thing is weighing you down. Even in those warm summer months, as soon as you get up high or down low near water, that chilly quilt or bulky old bag you've been using since high school is not cutting it. The Big Agnes Pluton UL is a highly compressible sleeping bag with a cozy lining of incredibly lightweight and packable 850-fill DownTek insulation. It will keep you warm and keep your pack light, whether that's a backpack, bikepack or packraft.