NEMO's top-of-the-line backpacking bag for side sleepers, the Riff Endless Promise sleeping bag features premium down and an eco-friendly construction. One of NEMO's Spoon bags, the Riff offers extra room around the elbows and knees to make it easier for side sleepers to shift positions overnight while maintaining more of a mummy shape elsewhere to be more efficient and weigh less than a rectangular bag. It features impressive 800-fill down that's treated for water resistance, so we can have a lightweight, packable bag that's not as vulnerable to moisture killing its loft. Offering more temperature adjustments than other bags, the Riff also features Thermo Gill vents around the chest that we can open or close from inside the bag to add or subtract a few degrees to land on our ideal sleeping temperature. Finally, this sleeping bag is one of NEMO's Endless Promise products--which means it's 100% recyclable if we send it to NEMO at the end of its (first) life.