Alpha SL Pant Men's

$252 ~~$400~~ In stock

The new Alpha SL Pant from Arc'teryx sets a new standard for the ultimate ultra lightweight, durable, full side-zip, waterproof/breathable 3-layer GORE-TEX® PRO ePE 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 GORE-TEX® rain pant available at our Feathered Friends Seattle Mountaineering Store.

Details

Hadron™ 3-Layer GORE-TEX® Waterproof/Breathable Gridded 20D Face Fabric. 94% Nylon, 6% Polyarylate with ePE and PU Membrane and 100% Nylon Backing. 78gsm. Bluesign® Approved Material. Liquid Crystal Polymer Ripstop.
N50d GORE-TEX® PRO ePE 3-Layer Fabric Reinforcements at Waist and Leg Cuffs. 94% Nylon, 6% Polyarylate with ePE and PU Membrane and 100% Nylon Backing. 99gsm.
Dope Dyeing Backer Process Uses Less Water and Energy
Full Length Fully Separating Side Zippers with Drop Seat
Non-Separating Zippered Fly
Reinforced Hems with Adjusters
Eyelets for Shock Cord Attachments at Leg Cuffs
Boot Lace Hooks
Low-Profile Waist Cinch Adjustment
Articulated Patterning
Gusseted Crotch
RECCO® Reflector
Waterproof
Breathable
Windproof
Ultra Lightweight
Durable
Extremely Versatile
Regular Fit
11.1 oz (314 g)

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Customer Reviews (5.0 / 5 · 5 reviews)

Leo ★★★★★ Oct 22, 2026

I was skeptical that a pant this light could hold up on rocky alpine terrain, but after three wet scrambles the 3-layer GORE-TEX PRO ePE hasn’t shown a single sign of wear. The full side zips make layering up or stripping down mid-route ridiculously easy, and it packs down small enough to forget it’

Robert D. ★★★★★ Oct 21, 2026

Having full side zips on such a lightweight shell means I can actually get these on and off over my hiking boots without a struggle. The fabric feels tougher than I expected given how insanely light the whole pant is. They stuff down tiny in my pack for unexpected alpine weather.

Evelyn J. ★★★★★ Oct 20, 2026

I was skeptical about how light these could be without feeling flimsy, but the 3-layer GORE-TEX PRO ePE holds up great on rocky approaches. The full side zips let me vent heat fast on climbs, and they stuff down small enough to forget they're in my pack.