The F1 XT is the perfect boot for expert ski mountaineers seeking an efficient yet streamlined product that?s ideal for touring with light equipment. The GRILAMID? FIBER GLASS shell features a full-length Lambda Frame for comfort, progressive flex, and torsional rigidity. The Carbon Grilamid? LFT cuff is paired with a Cam Buckle Power Strap to enhance power transmission and increase performance on the downhill while our new Overlap Shield Tech gaiter allows for easy entry and enhanced protection from the elements. A lower buckle works in unison with the Wave Lite Closure system for a secure, uniform fit over the entire instep without any pressure points. The F1 XT is the ultimate combination of touring efficiency and downhill performance in an ultralight package.