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 Unbelievabe! At 6'2 210 lbs, I recently purchased the Alpha SV Jacket [XL]; and the Alpha AR Pants [L] as a match set. Guiding remote Sub Arctic expeditons demands the best gear money can buy, I select hard shells as if my life depends on it, because in many cases it does, they represent our first line of defence against life threatening hypothermia. I'm totally impressed with the Arc'teryx product. The fit and articulation properties are exceptional providing absolute freedom of movement at all times. The workmanship is incredible, the pocket and leg zippers work flawlessly, the material is lightweight yet ultra durable, giving you the feel of extra confidence in adverse conditons. The breathability factor is like no other product I have ever owned, under extreme conditions, regulating my body temperature was never an issue. In a nutshell the Alpha AR Pants are worth every penny and more; I would highly recommended them to anyone looking for the best of the best. SRC.
Date published: 2014-11-05
Rated 5 out of 5 by from Diverse Performance Height: 5'10" Weight: 180lbs Pant Size: Medium Prior to purchasing these pants, I had a hard time deciding whether to purchase the Beta AR or the Alpha AR pants. After closely comparing these two products, I decided to go with the Alpha AR. Although the Alpha AR is only 30 dollars more, the pants out perform the more popular Beta AR in all aspects (Performance, Strength, and Fit/Style). The Alpha AR is equipped with more features such as the leg wrap, integrated belt, suspenders, etc. Also, the materials are more durable and the pant is an athletic fit in comparison to the regular fitted Beta AR. The regular fit looks much better in the urban setting in comparison to the much baggier Beta AR, yet the athletic fitted Alpha AR does not compromise mobility, hence the design for climbing. The Alpha AR leaves plenty of room for a base layer and mid-layer if needed making it just as useful for snow sports as the Beta AR. Anyways, enough about the Beta AR. The Alpha AR only has two negative aspects. 1) The pant only comes with a regular inseam (which may limit the consumer scope). 2) The lace hooks cannot be removed when they are not needed and can be quite annoying at times. The N80p-X and N155p-X GORE-TEX materials offer excellent durability when travelling through thick brush (but not durable enough to withstand a recent accidental crampon puncture to inner knee area which is understandable), but remain very breathable. The side leg zippers can be easily adjusted (open/closed) to increase breathability during high output activities. The Keprotec panels on the insteps have prevented crampon snags on multiple occasions. My favourite feature of the pant is the internal leg wraps. The leg wraps essentially sucks the material near the inner calf-knee against your skin to prevent crampon snags (simple but very effective). The large pocket can fit multiple items and sits just below the harnesses leg cuffs. Although the pants come with removable suspenders, I have rarely used them because of how well the integrated belt works. The sleek design of the Alpha AR while wearing a harness leaves no pressure of hot spots at all.
Date published: 2015-12-21
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Questions & Answers

What is the primary difference between the Alpha pants and the Beta pants?

Asked by: Yousaywhat
​The Alpha AR pant uses a Gore-Tex N155p Pro 3L material that is exclusive to Arc'teryx. It is engineered for high impact and abrasion resistance.
Answered by: REIservice
Date published: 2017-08-30

what's the inseam length in a large?

Asked by: nchargeny23
​The inseam for size large is 31 1/8"/79cm.
Answered by: REIservice
Date published: 2016-12-12
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