Free shipping Australia wide on orders over $99 | Over 400,000 Trees Planted
Free shipping Australia wide on orders over $99 | Over 400,000 Trees Planted
October 09, 2014
We aren’t talking about a fancy dress onesie, we are talking about a custom made, down filled, weatherproof onesie. A onesie warm and protective enough to keep you alive in the most severe alpine conditions on earth.
In 2013 mountaineer and Mont Ambassador Chris Warner came to Mont with a request; an outfit to assist him on his ascent of the highest peak in the Karakoram Range, the volatile and demanding K2.
Mont designers knew there was going to be nothing funny about this onesie.
Let us take you on a tour of the user-focused Mont design and manufacturing process at Mont HQ in Canberra, Australia.

Chris wearing the first sample made from basic measurements previously taken of him.
After getting a feel for the suit, Chris gave his feedback on the form, function and fit. Adjustments to the pattern were made, and the real suit production begins.

The pattern pieces are expertly cut by Danny from a roll of waterproof, windproof, breathable Hydronaute XT fabric.

Mont machinist Saun constructs the intricate shell of the garment. The shell includes articulated elbows and knees for ease of movement, reinforced ankle cuffs, knees and seat, down filled draught tubes to seal gaps in the zip, elasticated cuffs, internal and external pockets, lightweight mesh to divide down chambers (baffles) and drawcords to seal off all possible escape of warmth when the temperature dives.

Each down chamber or baffle in the empty shell is filled with calculated weights of pure goose down with a minimum loft rating of 800.

Trims, zips and drawcords are added to complete the garment. Inset: Mont Pattern Maker Kaleen makes some measurements to check everything is in order.


Chris Warner at high altitude in Pakistan wearing the Mont High Altitude Down Suit, the ultimate onesie.
Production photos by Kirill Talanine.
Expedition photos by Chris Warner.


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December 15, 2025
We were probably twenty electrolyte tablets deep each, feeling more like science experiments than cyclists. Add in sketchy tarmac with trucks roaring past, hogging the whole shoulder, and you had a section that demanded laser-sharp focus…
October 31, 2025
I had brought my Mont Helium 680 with me. A luxurious bag rated to -12°C for warm sleepers, it is perfectly suited to Tasmania’s cooler months. Ice crusted the ground and tent the next morning and checking my temperature sensor I was surprised to see that the temperature had dropped to -7.7°C overnight. That is remarkably cool for late October in Tassie!
October 20, 2025 2 Comments
At Mont Adventure Equipment, we believe that quality gear, people, and the planet deserve care. That’s why we only participate in only one yearly sale event that falls on Black Friday.