The Crestone ULLR men's winter boots are designed for warmth and performance in cold weather, whether you're hiking around a ski resort or clearing your driveway. They are insulated with PrimaLoft® for warmth and have a thermal rating of 30-40°C/-22/-40°F. The boots are waterproof with sealed seams for added protection. The sole features a special design for superior grip and traction on slippery, cold surfaces. These boots incorporate sustainable materials, including 100% recycled laces, polyester straps, and lining, along with 30% recycled rubber and EVA midsole. Over 60% of the upper is also made from recycled materials. Key features include PrimaLoft® 200 grams insulation and certifications for a -30°C / -40°C (-22°F / -40°F) thermal rating, and are PFC free. Specifications: Weight: 530.0 g.