Paddlers needing maximum insulation for those frigid adventures will appreciate the warm and breathable NRS H2Core Lightweight Union Suit. Its H2Core Expedition fleece offers comfort under a drysuit.

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Harnessing the warming power of Heatwave™ technology, the men's Seirus Heatwave Lite Reversible base layer bottoms reflect heat back to your body, and are now available in a lighter-weight design.

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Harnessing the warming power of Heatwave™ technology, the men's Seirus Heatwave Lite Reversible Long-Sleeve base layer top reflects heat back to your body, and is now available in a lighter design.

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Harnessing the amazing warming power of exclusive Heatwave™ technology, the men's Seirus Heatwave Reversible base layer bottoms reflect heat back to your body to keep you warm on cold-weather outings.

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Harnessing the warming power of Heatwave™ technology, the men's Seirus Heatwave Reversible Long-Sleeve Crew base layer top reflects heat back to your body to fend off winter's chill.

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Built for a wide range of sports and outdoor activities, the Saxx Hot Shot boxer briefs come equipped with highly breathable, quick-drying DropTemp™ tech to keep you cool when temps are high.

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Pack less and do more with the men's Mons Royale Icon Raglan top. You'll go from bike laps to alpine climbs and everything in between without having to change shirts.

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Designed to layer under pants or shorts, the men's Smartwool Intraknit Active base layer bottoms help with temperature regulation and moisture management to keep you comfortable while you're active.

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With mesh ventilation for cooling, minimal seams to help reduce chafing and a fit that moves with your body, the men's Smartwool Intraknit Active base layer top is ready to go the distance with you.

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With merino comfort, ventilation and articulated flex zones, the Smartwool Intraknit Thermal Max Quarter-Zip base layer top will be what you grab first for high-intensity, cold-weather adventures.

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Stay comfortable on cooler-weather adventures in the Smartwool Intraknit Thermal Merino men's 3/4-length base layer bottoms, which have a performance-enhancing design and a shorter, versatile length.

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The winter-ready pants you need to perform all season, the men's Smartwool Intraknit Thermal Merino Base Layer 3/4 Bottoms use merino wool to help keep you comfortable on every cold-weather outing.

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Built to flex and follow you like a shadow, the men's Smartwool Intraknit Thermal Merino base layer bottoms put warmth first, while 3D knit mesh ventilation helps keep you dry and comfortable.

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Adventure all day in the cold with the enhanced breathability of the men's Smartwool Intraknit Thermal Merino Colorblock Crew base layer top, designed with body-mapped mesh and distinctive patterning.

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