The F1 LT Alpine Touring Boot is Scarpa's lightest ski boot that best-suits ski mountaineers and high-mileage backcountry tours. Carbon-infused Grilamid grants a forgiving 100 flex at a ridiculously low weight of two pounds and two ounces. Scarpa's 3D Lambda Torsion Frame maintains flex throughout the boot for enhances downhill performance. On the ascent, the boot's Speed Lock latch initiates an impressive range of motion for easy hiking. At the summit, a single buckle and Boa's glove-friendly dial help you transition quickly. The ultralight, ultra-breathable liner has a waterproof gaiter to keep comfortably dry when you're setting the skin track through deep powder. Although the brand's size chart has recommendations for how to choose your size, customer feedback suggests this shoe runs small, we would suggest sizing up if you are unused to a tight performance fit.