How complicated can it be to get a good night's sleep? At high altitude and/or in extreme cold, its not as easy as it sounds, even if you are exhausted. This is why Mountain Equipment have invested so much technology into their top of the range bags, designed for the most serious environments on the planet.
Their finest, 850 Fill Power, ethically sourced down, is held in position by a complex construction of baffles that ensures the down remains where it should and doesn't migrate into inefficient clumps. Particularly special attention has been paid to the head and foot of the bag, because your head generates so much heat and your feet are the first to feel the lose of it. There are a total of 14 baffles in these two areas alone. Across the torso and legs the V and trapezoid baffling is combined with Mountain Equipment's EXL system that has been developed to hug your body with its elasticated lining that closes up gaps in-between you and the bag, minimising cold spots, maximising down loft and adding an extra 2 degrees warmth with no weight penalty.
The expedition fit of the bag allows for the additional bulky clothing you are likely to wear inside the bag as well as other items you want to keep warm like your boots and your water bottle (quenching your thirst with an icicle at 2am is no one's idea of fun).
Of course bringing things inside the bag can add to the wear so a hard wearing 40 denier fabric lines the inner. At the foot and head the inner is made from the same Drilite Loft used for the outer. This lightweight, water resistant shell fabric has a Hydrostatic Head of 1500mm meaning its ideal for repelling moisture that could be generated by snow melting off your equipment.
Other unique features include ground level seams that maximise warmth on the sides of the bag and a Gemini collar with down draft tubes that keep your neck warm and heat from escaping out of the hood.
With all this heat retention you may find you want to unzip in a hurry if you awake overheating. Reassuring then, to know the ¾ length zip has an anti snag baffle too.
Mountain Equipment declare they have been making the best sleeping bags in the world for 50 years, quite a boast you might think but they've got the credentials to prove it. Used on expeditions to every one of the fourteen 8,000 metre peaks and in both polar regions, their range of Extreme bags leans heavily on the immense experience gained by thousands of adventures tackling the most challenging routes. The 'unclimbable', 'unconquerable', 'impossible' that have all been overcome by determination, skill, endurance and - good kit.