The-Sidi-Crossfire-boot-is-highly-comfortable-Designed-with-a-dual-flex-system-which-coupled-with-four-independent-floating-straps-offers-the-rider-a-supremely-personal-fit-Additional-to-this-is-the-adjustable-calf-system-which-allows-you-to-exp&-the-diameter-of-the-Crossfire-at-the-calf-to-accommodate-knee-braces-or-thick-calves-The-entire-upper-portion-of-the-boot-is-re-buildable-In-fact-you-can-customize-the-colors-of-your-Crossfire-by-buying-different-color-spareparts-Features-Upper-in-full-grain-leather-&-Synthetic-Leather-Lined-with-Cambrelle-&-air-Teflon-mesh-Replaceable-shin-plate-Micro-Adjustable-buckles-Anatomically-shaped-heel-Adjustable-calf-system-Dual-Flex-system-Toe-area-Anatomically-shaped-heel-Boot-leg-Metatarsus-protection-Rubber-sole-Nylon-inner-sole-with-removable-arch-support-All-parts-of-the-boot-can-be-replaced