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Meet the Beneunder TrueWarm Baselayer — built for fast-dry warmth in extreme cold. Designed with HeatApex Core insulation and 3D-Vents sweat channels, it keeps you dry, locks in heat, and moves with you. Ideal for high-output outdoor activity, it withstands damp chill down to -15°C.
Highlights：
- HeatApex Core: rapid sweat-wicking, long-lasting warmth
- Withstands cold as low as -15°C
- 6-second quick-dry fabric, stays fresh under pressure
- 3D-Vents sweat channels keep body dry during intense movement
- Flexible 360° stretch knit for unrestricted motion
Yarn 1: 59.8% Acrylic, 40.2% Viscose – soft, breathable, and warm, providing natural comfort and lightweight insulation.
Yarn 2: 83.1% Polypropylene, 16.9% Spandex – stretchy, quick-drying, and moisture-wicking for active performance.
Yarn 3: 100% Polyester – durable, smooth, and easy-care, enhancing shape retention and wearability.
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Based on moderate activity with a basic inner layer; increase warmth for wind or humidity.
Recommended range: down to -15°C / 5°F
6-Second Quick-Dry — No More Cold Sweat
With moisture-wicking fibers, sweat evaporates in just 6 seconds. Unlike ordinary thermals that stay wet and heavy, this baselayer keeps you dry and comfortable through high-output activity.
Withstands -15°C Cold — Lasting Heat Retention
HeatApex Core locks in warmth, sustaining comfort even in temperatures down to -15°C. Tested for outdoor performance, it provides 35% better heat retention than standard thermals.
3D-Vents Sweat Channels — Stay Dry in Motion
Strategically engineered 3D sweat channels accelerate evaporation in high-sweat zones like chest, back, and underarms. Even during intense exertion, your skin stays fresh and dry.
InfraHeat Fibers — Warmth on Contact
Infused with far-infrared fibers, the fabric absorbs body heat and releases it back, boosting skin temperature by up to +1.8°C for instant warmth.
360° Stretch Knit — Flexible Without Limits
Made with seamless 360° stretch knit, the SK001 adapts to every move — from bending to sprinting — without restriction. Soft and close-fitting, it’s designed for active outdoor performance.