The Most Superior Sleeping Bag I Have Ever Used

by Claire Mackay

The Most Superior Sleeping Bag I Have Ever Used

When Australian adventurer Claire Mackay set off to summit Aconcagua in the Andes mountain ranges of Argentina earlier this year, her biggest fear was the bitter-cold nights. Mountain Designs equipped her with the UltraTek 900 down sleeping bag, knowing it was purpose-made for exactly these types of adventures. Read on for Claire's review and find out why the UltraTek 900 will now be seeing plenty more of her future mountaineering adventures.

UltraTek 900 Down Sleeping Bag

When I travel to the mountains, my biggest fear and obstacle is coping with extremely cold temperatures. I feel the cold easily and find it very hard to stay warm, so when I look for insulation equipment, I look for the best-of-the-best when it comes to quality! If anyone is looking for a sleeping bag suitable for high altitude expeditions or extreme temperatures, then they need not look any further than the Mountain Designs UltraTek 900 down sleeping bag. This sleeping bag is by far the most superior I have ever used. I recently took this piece of equipment to Aconcagua in Argentina, which is renowned for hostile, subzero temperatures, and I felt hugely relieved to have such a warm sleeping bag to climb into at night.

Snug As A Bug
UltraTek 900 Sleeping Bag

Snug as a bug: Claire stayed cosy in the UltraTek 900 (left) through the technical mummy shape, trapezoidal baffling construction, and 3D hood design with face baffle (right). (Image courtesy of Sofia Jin)

It has a comfort rating of -17°C and an extreme rating of -39°C, with 750 loft, RDS-certified duck down to insulate you from the cold wind and ice. The down itself is treated with DownTek for water-resistance, ensuring it doesn't clump and can continue to insulate even in damp conditions. The long mummy shape is spacious but snug, contoured but comfortable, you can really feel the warm air getting trapped inside for insulating. I wore just one pair of thermals and was cosy all night. This bag is also extremely lightweight and compressible for its warmth, weighing in at just 1,300 grams, and packing down easily. I will definitely use this sleeping bag for future 8,000-metre expeditions to the Himalayas that I have planned.

Photo Credits

Images supplied by:

Claire Mackay

Sofia Jin




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