The Merrell Women’s Siren 4 Thermo Mid Zip Waterproof Boot is a winter-ready boot with a women’s-specific fit that combines function and all-day wear-ability. Best for: Winter Hike Insulation: 200 grams Primaloft® Gold Eco Series synthetic insulation. SOLARCORE® Aerogel insole provides underfoot superior warmth while being extremely flexible and ultra-thin. Waterproofing: Waterproof full grain leather upper, complete with a waterproof membrane seals out water and lets moisture escape. Traction: Vibram® Arctic Grip™ All Terrain outsole designed to effectively extend the winter traction season, due to the enhanced durability and versatility.Comfort Features: • Heavy-duty, Waterproof, YKK zipper for easy on and off • Protective and abrasion resistant rubber toe cap • Cleansport NXT™ treated for natural odor control • FloatPro™ Foam midsole for lightweight comfort that lastsMaterials: • Waterproof full grain leather and knit upper • 100% recycled laces and webbing • 100% recycled fleece lining • 100% recycled mesh footbed cover • 5% recycled PU removable footbedAdditional Measurements: • Stack Height: 28.5-20.5mm • Drop: 8mm • Lug: 5mm • Half pair weight: 1lbs-3.04oz, 540g Merrell Women’s Siren 4 Thermo Mid Zip Waterproof Boot Tobacco