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Zpacks Octa Fleece Thermal Bottoms

Zpacks Octa Fleece Thermal Bottoms - Main image
$63.97 $99.95 In stock

Zpacks Octa® Fleece Thermal Bottoms beat the warmth and weight of all other long underwear in their class. Designed to be worn under your hiking pants in frigid weather, under shorts in cool weather, or worn as an ultralight sleep layer, these leggings are unmatched when ounces count.

Octa® Fleece features a soft, fluffy interior that traps warmth and keeps you cozy, and an abrasion-resistant exterior that withstands wear and tear.

Check out the rest of our Octa® Fleece Collection here.

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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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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)

Claire ★★★★★

Wore them under my hiking pants during a 20-degree morning and my legs stayed warm without any bulk or bunching under the fabric. They're so streamlined I forgot I had them on by the second mile, which is exactly what I want from thermal bottoms.

Victoria ★★★★★

These feel almost impossibly light in my pack, yet they kept me toasty on a freezing morning hike under my regular pants. The stretch and cut let me move freely without any bunching, and they’ve become my go-to for cool-weather camp lounging too.

Richard ★★★★★

Wore these under my shell pants on a freezing ridge traverse and barely felt the cold even with a stiff wind. The octa fleece inner traps heat without any of that clammy feeling I get from my old base layers, and they slid right under my hiking pants without bunching up. Only complaint is they’re so