Alpha Pant Men's S25

$217 ~~$350~~ In stock

The new Alpha Pant from Arc'teryx sets a new standard for the ultimate ultra lightweight, durable, full side-zip, waterproof/breathable 3-layer GORE-TEX® pant. Made with ultralight liquid crystal polymer ripstop Hadron™ gridded face fabric with double the abrasion resistance of other fabrics twice the weight. An innovative waist cinch customizes the fit and rides comfortably under a climbing harness or pack hipbelt. The full length side zippers make these extremely easy to put on and take off while wearing things like boots and crampons, making these the ideal light and fast mountaineering pants. This is the lightest weight full-side zip rain pant available at our Feathered Friends Seattle Mountaineering Store.

Details

Hadron™ 3-Layer GORE-TEX® Waterproof/Breathable Gridded Face Fabric. Bluesign® Approved Material. Liquid Crystal Polymer Ripstop.
N40d GORE-TEX® PRO Most Rugged 3-Layer Fabric Reinforcements at Waist and Leg Cuffs
Dope Dyeing Process Uses Less Water and Energy
Full Length Fully Separating Side Zippers with Drop Seat
Zippered Fly
Laminated Instep Patch Guards
Eyelets for Shock Cord Attachments at Leg Cuffs
Low-Profile Waist Cinch Adjustment
Articulated Patterning
Gusseted Crotch
Waterproof
Breathable
Windproof
Ultra Lightweight
Durable
Extremely Versatile
Regular Fit
7.8 oz (220 g)

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Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Brian ★★★★★ Oct 22, 2026

The liquid crystal liner breathes so well that I didn't overheat during a steady uphill climb, yet it kept me completely dry in a sudden downpour. The side zippers make putting them on over boots effortless.

Ruby I. ★★★★★ Oct 21, 2026

The full side zippers are a lifesaver—I can pull them on over boots without taking my shoes off. They're incredibly light but feel surprisingly tough against brush and sharp rocks.

Emily ★★★★★ Oct 19, 2026

Finally got the chance to test these in a proper downpour and the full side-zip is a game changer for quick changes without taking off my boots. The 3-layer material feels surprisingly light on, not like the stiff shells I've worn before. They pack down so small I forgot they were in my daypack.