The HFS runs small. A new lightweight, breathable mesh upper, a new tire tread-inspired sole, a silky moisture wicking lining made with 37.5 material, protected tension straps... put all of that together for your new favorite road running shoe, the Xero Shoes HFS. Vegan-friendly materials. Natural FIT - a wide toe box lets your toes spread, splay, relax, and function naturally. Flexible enough to let your feet bend, move, and flex the way, well, that feet are supposed to. You can remove the 2mm insole, for a closer-to-barefoot experience that lets you Feel The World.Light weight - so light, in fact, you could forget you have them on. Huarache-inspired design - the adjustable instep and midfoot straps are not just eye-catching but functional, giving you a secure and comfortable fit. EVA footbed. The XERO-drop design (non-elevated heel) allows for proper posture, and it's built low to the ground for balance and agility. Natural FEEL - the HFS has a 5.