While most of Himali’s garments are made for the high country, the Boulder-based mountaineering brand’s 8000 Meter Down Suit is built to operate on an entirely different level. Literally. The company’s American and Nepalese Sherpa co-owners used their decades of climbing and guiding experience to design their ideal outfit for navigating the world’s tallest mountains. Here’s what makes their suit’s latest iteration ($2,000) perfect for the Death Zone—the region above 26,000 feet where there’s little available oxygen and the weather wants to kill you.

1. Himali co-owner Ed Viesturs, the only American to summit every 8000er without supplemental oxygen, knows moving fast is essential. So Himali sourced a lightweight fabric that uses interlocking, diamond-shaped threads to create a strong, ultratight weave. At just more than three and a half pounds, it’s one of the lightest suits on the market.

2. Early versions featured overlapping layers on the chest, each with its own zipper, for extra wind protection, but Mingma G. Sherpa, a leader of the first winter ascent of K2 in 2021, felt the second zip weighed too much. The new version uses a single-zip design.

3. As guides, Sherpas perform plenty of duties that require ungloved fingers. Co-founder Tendi Sherpa, a renowned mountaineer who’s summited Mt. Everest 15 times, requested that the suit include insulated chest pockets so he’d have an easy place to warm his bare hands between tasks.

4. Himali co-owner Ed Viesturs, the only American to summit every 8000er without supplemental oxygen, knows moving fast is essential. So Himali sourced a lightweight fabric that uses interlocking, diamond-shaped threads to create a strong, ultratight weave. At just more than three and a half pounds, it’s one of the lightest suits on the market.

5. Wearing a prototype on Nepal’s 26,781-foot Manaslu, Tendi Sherpa noticed that his body heat was melting snow caught between his pack and his back and moisture was seeping into the suit. To prevent frostbite and hypothermia, the get-up now has a fully waterproof outer layer, something few competitors can say.