La Sportiva Lhotse Mountaineering Boot - La Sportiva's Lhotse GTX is a winter mountain and work boot designed to provide serious foot protection. These boots are insulated and waterproof to keep the feet warm and toasty. They feature a 3.0 mm silicone impregnated Idro-Perwanger roughout leather exterior upper for excellent durability and foot protection. An 8mm MtnFlex insole provides enough stiffness to work well with automatic crampons. The durable soles also protect the feet from rough terrain.