Alpha Insulated Pant

$504 ~~$700~~ In stock

The Alpha Insulated Pants from Arc'teryx are lightweight and extremely warm expedition hybrid 850 fill goose down and synthetic Coreloft™ insulated pants with fully separating side zippers and seam-taped extremely lightweight and strong 2-layer GORE-TEX® INFINIUM™ Hadron™ proprietary outer face fabric that is engineered with a liquid crystal polymer ripstop that makes this fabric as abrasion resistant as many other fabrics twice the weight. The GORE-TEX® INFINIUM™ fabrics also block the wind while trapping and holding in more warmth than standard fabrics. Other features include a belay loop compatible fly, harness accessible zippered thigh pocket, and hem adjusters to seal out snow and debris. Designed for extremely cold bivouacs and alpine belays.

Details

2-Layer GORE-TEX® INFINIUIM™ N30p Outer Face Fabric
2-Layer GORE-TEX® INFINIUIM™ N20p-LCP Liquid Crystal Polymer Reinforcement Fabric in High Wear Areas
850 Fill European Goose Down
Coreloft™ Continuous Synthetic Insulation in Moisture Prone Areas
Fully Separating Side Zippers for Easy On and Off while wearing boots, crampons, or skis
Belay Loop Compatible Fly
Harness Accessible Zippered Thigh Pocket
Hem Adjusters to Seal Out Snow and Debris
Windproof
Highly Water Resistant
Highly Breathable
Lightweight
Durable
Extremely Warm
15.3 oz (434 g)

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Standard Shipping · United States: $0.00

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)

Aurora E. ★★★★★ Oct 22, 2026

I can zip the side open fully without taking off my boots—perfect for quick layer changes on the trail. The 850 fill down keeps me toasty even in single-digit temps, and the fit isn't bulky at all.

Nicholas ★★★★★ Oct 21, 2026

These pants have held up perfectly on my last two trips; the combination of down and Coreloft insulation kept me comfortable even when the temperature dropped below zero. The lightweight feel is remarkable for how warm they are.

Joshua Z. ★★★★★ Oct 20, 2026

The fully separating side zippers are a game-changer for putting them on over boots without losing heat. They felt incredibly warm during my winter camping trip, yet remained light enough to pack easily.