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CoreHeat Expedition Layer
High-output thermal regulation for extreme alpine environments.
4.9 · 7 reviewsEarn 444 TrekX points
The CoreHeat Expedition Layer is a performance-focused thermal baselayer engineered for mountaineering, glacier travel, and severe cold-weather alpine movement. Constructed with advanced merino-synthetic hybrid fabrics and body-mapped thermal zones, it delivers exceptional moisture control, warmth retention, and breathable comfort during mountain activity. Designed for elite expedition layering systems, it provides reliable next-to-skin thermal performance in demanding sub-zero environments.
Ideal for
- ◆High-altitude expeditions
- ◆Ice climbing systems
- ◆Severe cold-weather movement
- ◆Technical alpine layering
Colour: Earth
Select SizeRequired
Specifications
FABRICMerino wool & graphene-infused synthetic blend
WEIGHT≈ 280g
THERMAL STRUCTUREBody-mapped thermal regulation zones
FITCompression-inspired alpine fit
MOISTURE MANAGEMENTHigh-output sweat transfer system
SEAM CONSTRUCTIONFlat-lock anti-friction seams
ODOR CONTROLNatural merino antimicrobial properties
BREATHABILITYVentilated airflow knit panels
LAYERING SYSTEMDesigned for expedition shell integration
CERTIFICATIONbluesign® approved materials
Product Deep-Dive
D.01
How It’s Made
The CoreHeat Layer combines fine merino wool fibers with graphene-enhanced synthetic yarns engineered to improve thermal efficiency, durability, and moisture transport during alpine movement.
D.02
Advanced Thermal Regulation
Body-mapped insulation zones help retain warmth in critical exposure areas while improving airflow and breathability during high-output climbing and trekking.
D.03
Moisture & Sweat Management
The hybrid fiber architecture rapidly moves perspiration away from the skin, reducing heat loss and improving comfort during prolonged alpine activity.
D.04
Expedition Layering Compatibility
The low-profile compression-inspired fit integrates seamlessly beneath insulated midlayers and expedition shells without restricting movement.
D.05
Long-Duration Alpine Comfort
Flat-lock seam construction minimizes friction and pressure points during extended use under harnesses, packs, and technical layering systems.
D.06
Intended Use
Designed for alpinists and expedition athletes requiring high-performance thermal baselayers for severe cold-weather mountain environments.
Daily essentials, always ready
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Customer Reviews
4.97 reviews
5
86%
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14%
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Leila KovacSeoul, South Korea
Mar 2026
Made longer trips noticeably easier
I tested the CoreHeat Expedition Layer long enough to notice both the strengths and weak spots. The difference became clearer once conditions changed, because performance became more obvious once conditions stopped being forgiving. The technical nature of the product assumes a bit of prior experience. This became one of those products I stopped thinking about because it simply worked.
Verified purchaseSara DuboisZurich, Switzerland
May 2025
Exactly the kind of gear I hoped for
My goal was simple: see if the CoreHeat Expedition Layer held up during cool morning starts followed by warm afternoon hiking. I noticed pretty quickly that it performed consistently during cold starts, steep ascents, and long descents. The confidence factor ended up being higher than expected.
Verified purchaseElena BaumannTrento, Italy
Dec 2024
Comfortable, practical, and trail-ready
I bought the CoreHeat Expedition Layer with realistic expectations rather than hype. The more realistic conditions became, the more the technical features felt practical rather than included for marketing reasons. It became easier to appreciate over time. It quietly justified its place in my gear rotation.
Verified purchaseTobias RomanoTromso, Norway
Nov 2024
Performed exactly how I hoped
The CoreHeat Expedition Layer ended up joining me for a cold descent after a high-output climb. After repeated use, the details feel designed by people who actually spend time outside in difficult conditions. I could see experienced users wanting one or two more refinement details. I can see this lasting a long time in my kit.
Verified purchaseTrekX reply
Thanks for taking the time to leave such thoughtful feedback after real use.
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CoreHeat Expedition Layer