Layer up for a cold day on the mountain. Stay warm at base camp. The men's Burton [ak] Helium Stretch Insulated Pants are that extra layer that makes a difference on the coldest days. Stretchy and breathable, they're made for wearing under your shell pants or bibs, but they're so comfortable you'll prob wear them for a lot more things, too.

• Regular fit is just right: Not too tight or too baggy
• Made of stretchy and breathable lightweight 20D nylon and spandex plain weave, water-repellent coated fabric; [ak] DWR coating sheds light precipitation
• Thermacore Stretch [40g] insulation offers superior warmth-to-weight performance in a low-bulk design that won't restrict your movement, providing insulation that is designed to move with you and is made with bluesign® materials that are safe for people and the planet
• Breathable with light wind resistance for medium-intensity activities where breathability is a higher priority than wind resistance and added layering helps provide warmth.
• Elasticized waistband with internal draw cord cinch
• Stretch binding at cuffs
• Zippered back pocket and zippered hand-warmer pockets
• Made with bluesign® materials: produced with resource-efficient manufacturing processes and using only chemicals that are safe for people and the planet
• Lifetime Warranty