Sole: Features the Millennium 5 Carbon Composite Sole (or Millennium 4 in some versions), which is a nylon matrix infused with carbon fiber for stiffness and durability.Closure System: Uses a micro-adjustable Caliper Buckle ratchet for on-the-fly tuning, paired with two High Security Velcro straps that have integrated locking teeth to prevent slipping.Upper Material: Constructed from Microfiber Microtech (Technomicro), a synthetic material that is breathable, water-repellent, and resistant to stretching.Heel Cup: Includes a reinforced Sidi Heel Cup to stabilize the foot and prevent heel lift during hard efforts.Compatibility: Designed for standard 3-bolt road cleats (e.g., Look, Shimano SPD-SL, Speedplay). New in box - box has some wear from storage closet