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  • Constructed from N80p-X Gore-Tex Pro 3-layer, a face fabric 5 years in development, Alpha SV delivers exceptional durability, yet is supple and resilient
  • Engineered to shed water / snow and resist abrasion, the fabric face employs larger yarns that are very tightly woven to create a smooth but highly abrasion-resistant surface
  • Incredibly durable N155p-X Gore-Tex Pro 3-layer fabric reinforces high-stress areas
  • High-cut, breathable stretch-woven bib with quick-adjust suspenders offers coverage in the chest and the back, keeps snow and drafts out and helps retain essential body heat
  • 2 large, easily accessible bellowed laminated chest pockets lay flat when not in use
  • Taped seams for added weatherproofness; micro-seam allowance (1.6mm) reduces bulk and weight
  • Articulated knees and seat and gusseted crotch facilitate full range of motion
  • Watertight 3/4-length leg zippers stop below harness / hipbelt area
  • Watertight through-the-crotch zipper is harness compatible, minimizing exposure
  • Zipper garages protect zipper closure from snow and rain
  • Removable internal LegWrap minimizes fabric volume to reduce crampon snags
  • Laminated waist drawcord
  • Adjustable pant cuffs with stowable boot lace hook
  • Keprotec instep patches provide superior protection against damage by boots, crampons and ski edges; grommets at the hem
  • Note: watertight zippers are highly water resistant, but not waterproof; we do not recommend keeping items in your pockets that may be damaged by moisture


View all Arc'teryx Men's Mountaineering Pants

REI membership


Best Use Mountaineering
Fabric Nylon
Windproof Yes
Waterproof Yes
Type Of Waterproofing Gore-Tex Pro 3-layer waterproof breathable laminate
Bibs Yes
Powder Cuffs Yes
Inseam (in.) Unavailable
Gender Men's

Size chart

Sizing notes

SHORT: Some pants are available in short sizes, which generally means an inseam that is 2 inches shorter than regular sizes. TALL: Some pants are available in tall sizes, which generally means an inseam that is 3 inches longer than regular sizes.

Rated 5 out of 5 by from The best protection against all! The best protection against all! The performance of the pants are unprecedented, I have the pants of the line Mammut Extreme and not so comfortable ... The closure between legs has made a huge difference when you have to relieve ourselves in bad weather, be windy and cold. Pre-formed knees and makes a Stretch parties can move in every way and with great freedom. THIS IS DEFINITELY THE PANTS FOR BIG EXPEDICCIONES to the remotest THE PLANET!
Date published: 2011-09-01
Rated 5 out of 5 by from Awesome pants for skiing and climbing Have used these pants for a few years now and like the material update on the Alpha SV Bib pants/jacket that happened 2-3 years ago; it made skiing and hiking much quieter. I love the fit of these pants and the versatility of the pockets, side zips, and relief zip. I don't think a company could've invented a better pair of technical climbing pants. As a historical note, I am glad that these pants don't come with the slot for knee pads like the earlier versions of this pant -- I found the built-in slot for knee padding unnecessary and uncomfortable because the knee padding made the area around the knees poorly breathable.
Date published: 2015-07-22
Rated 5 out of 5 by from Gotham City Revisited Here`re the pants for Batman. It`s a very fine piece of equipment, almost bullet proof and yet not restricting your movement. I bought XL large instead of regular, it gives me more room for the insulation (Atom LT and maybe even Kappa). My comparison is: Some Sunvalley Gore XCR Freeski pants/bibs which i wore for the last 10 years and a Propper Gen2 Gore Tex trouser but they can`t reach for the Alpha bibs. It`s the durability and the zippers which make up for the big difference. If it`s getting to warm, just zip your legs open and vent out excessive moisture, if you feel the certain urge, there`s a crotch zip going all the way around so you don`t have to drop the pants. Another fine feature is the height, perfect for the cold, your underwear never looks out and the cold doesn`t come in. But don`t wear it while on high output activity, below -15C. The pants froze together with the Atom pants underneath and the whole stuff got useless. Also to mention are the knee pads, they can be very handy sometimes when skiing... The durability is astonishing, i went down on ice while skiing and also slid over some rocks but the pants remained unimpressed. Same goes for the jacket. In moments like that you realize that it was worth paying the xtra cash for this pant. Maybe some cons: The zipper on the legs should be separated in two pieces, one finishing just a few inches under the knee and the other should start a few inches above the knee. The zipper going from top to botom makes the pant unnecessarly stif around the knee. Enjoy
Date published: 2012-02-15
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