All new ankle pivot system is designed to have a hard limit of foot/ankle hyperextension. Sidi has upgraded the entire SRS sole system on the Crossfire 3 SRS boot. New sole boat features a more cupped and thicker design so the rider's foot rests deeper into the sole system. This change gives more engagement between the boots upper and sole in manufacturing which will extend the boots lifespan. This change also creates a firmer sole than any other Crossfire boot. Replaceable by hand tools, the new Dovetail SRS anti-skid rubber sole covers the arch area of the sole. Toe and heel areas on the new Dovetail SRS sole are now a permanent part of the Crossfire 3 SRS. A laminated Technomicro is used as the base material in all areas. Slim, cool non-bootie design. Calf plate system features an inner double adjustment that expands to fit even the largest calf or knee brace system! Nylon insole no dangerous steel shank! Inner heat shield made of high grip material. New inner boot gaiter has a larger circumference than the Crossfire 2 making for a tight seal around the rider's lower leg no matter which knee brace system may be used. Upper inside of the gaiter features an anti-heat suede protection-grip panel. Removable arch support. Toe area covered in protective plastic. An all new rigid, shock resistant, anatomically shaped heel hold the riders foot firm and thus resists twisting while offering added protection. Replaceable, sleek, micro adjustable cam lock buckle system with memory retention nylon straps. All buckles move independently of each other and have just one fixed point (by a screw). This allows an easy closure and the buckles can adapt to the rider's position as they pivot on the mounting screw as the rider changes position on the bike. Lower buckle guards help protect against opening due to an impact. The complete central strap system can be easily replaced. Lined with anti-abrasion Cambrelle in the foot area for comfort, the upper is lined with Teflon mesh which prevents complete absorption of water and sweat. These materials will not retain water or sweat on the inside of the boot. The boot will dry quickly and the treatment also prevents the onset of mold. All bolt-on parts are replaceable. Sidi patented replaceable shin plate. Malleolus external plastic guard with ergonomic closed cell foam padding internally to enhance protection of those tender small foot bones. Innovative Dual Flex System upper offers the industry's best fit, especially with knee braces! Assembled and replaceable boot leg is stitch free! Replaceable inner kick starter/foot peg nylon guard on the inside area of both boots. The boot leg is fully assembled with screws, is stitch-free and entirely replaceable.