Stuffed with 800-fill European goose down, the Rab Neutrino 400 Sleeping Bag delivers three-season warmth without weighing a ton or taking up tons of precious pack space on light-and-fast climbing missions and minimalist backpacking trips. Rated down to 27-degrees Fahrenheit (European Lower Limit), this down-filled bag is ideal for chilly autumn evenings in the desert and summer nights camped at high elevations. Rab's own Sleep Limit rating of 25-degrees Fahrenheit (based off European Standard + user testing) means it'll suffice when the mercury plummets well below the forecast's prediction. Water-resistant Pertex Endurance fabric prevents outside moisture from seeping through and compromising the down's heat-trapping loft. Going one step further, the down insulation features a hydrophobic coating that repels condensation and built-up perspiration from clumping together its lofty down clusters. Close-fitting neck baffles seal-in fiery heat, with trapezoidal baffle chambers throughout the body eliminating cold spots from stealing warmth. As a cool bonus, this bag zips into other Neutrino bags when you're camping with your significant other, favorite pooch, or simply desire double the sleeping space.