Choose your adventure in the thermal trail running sock crafted to make winter feel a whole lot warmer. Keep toes toasty on your journey in a lighter sock engineered with Thermolite T3 Ecomade insulated fibers that provide sustainable, long-lasting thermal insulation and comfort without the extra weight. Go further in all conditions with blister-resistant yarn where you need it most, and anatomical left/right specific design for the perfect fit on the trail.