Technical mountaineering calls for a fully featured boot to get us up and down the mountain safely. The La Sportiva Trango Pro GTX Boo is one of our favorite lightweight mountaineering boots and has a lightly insulated construction for three-season mountaineering and a completely waterproof construction utilizing GORE-TEX technology. The Synthetic upper fabric incorporates a hydrophobic honeycomb fabric technology to warm off abrasion, shed water, and maintain durability for many miles to come. the TOU and PU midsole offers fatigue-reducing support and comfort for our feet, while the GORE-TEX Performance Comfort lining combined with the carbon-filled nylon insole ensures comfort and warmth. This boot has a super gaiter construction and uses both laces and a quick closure hook-and-loop collar to keep out the debris.