Sidi Kaos Air ShoesSidi's quality and finishing design come as part and parcel of the brand. Lightweight and performance-ready, these Kaos Air Shoes are ideal for the racing cyclist who is looking for a performance-boost or for the club cyclist who appreciates a high-quality, breathable, road shoe without sacrificing on comfort Kaos Air Shoes: Stiff Carbon PerformanceA Millenium 4 Carbon Composite Sole provides a stiff foundation for power transference and is both durable to stand the test of time and non water-absorbent. Wear Sidi's Kaos Air Shoes throughout the season and they'll still be in great condition to deliver the same performance next year These shoes also feature Sidi's Soft Instep 2 technology for an ergonomic fit alongside great breathability properties to keep your feet comfortable. The Kaos Air has a fixture system that keeps your feet secure whilst offering gradual adjustments for tweaking 'on the fly' when it comes to a bunch sprint or a steep climb. Stay calm in the chaos of the peloton with comfortable feet Features:Please Note: Sidi recommend purchasing one whole size up from your usual fitMaterial: Carbon Composite (Sole); Vented Politex (Upper); Polyurethane (Heelpad)Sole: Millenium 4 Carbon Composite SoleDurableBreathableComfortableSecure closure systemWeight: 325g (per shoe, approximately)Technologies:Millenium 4 Carbon Composite Sole: The Millenium 4 Carbon Composite Sole features injected carbon fibre in a matrix of Nylon, providing more rigidity than a standard nylon sole. The Millenium 4 Carbon Composite Sole is also more durable, completely non water-absorbent and mechanically stable, meaning it’s less susceptible to changes in stiffness resulting from aging, prolonged usage, and changes in temperature or humidity. An anti-slip toe insert and replaceable polyurethane heel pad are incorporated into the Millenium 4 Carbon Composite Sole, for walkability. The Millenium 4 Carbon Composite Sole uses a standard 3-hole drilling pattern for compatibility with the best pedal systems available, and includes a printed 10mm lateral and fore/aft cleat alignment scale on the sole as well as the Look Memory Eyelet for easy cleat alignment and replacement Politex: The Politex material is constructed from several overlapping layers with different physical-mechanical properties. The compacted PVC is coupled with two fabrics (knitted fabric + felt) that is then film dyed for long-lasting colour retention. Politex offers strong resistance to ripping, laceration, stretching and fading. Politex is made in strict compliance with European regulations and is a totally "green" product Caliper Buckle: The micrometric closure called "Caliper Buckle" is adjustable by lifting the central buckle. In order to completely open, lift together both side buckles, or push the centre button to slightly loosen one tooth at the time. The system is also adjustable during a race Soft Instep 2: The Soft Instep Closure System is a wide, anatomically curved strap combined with a soft, thermoformed EVA pad that distributes pressure evenly over the instep area. The Soft Instep Closure System is adjustable from both sides, to perfectly centre the EVA pad over a high or low instep. The system eliminates the need for the High Instep Extender. This system is replaceable Sidi Heel Cup: Reinforced cup that stabilises and supports the heel. Anatomically shaped plastic, reduces heel slip and provides increased power transfer. Provides additional foot protection in the event of a crash Replaceable Heel Pad: For walkability, Sidi cycling shoes include a replaceable polyurethane heel pad Tecno-3 System 3: Sidi's Techno-3 System dials in fit along the entire length of the shoe, adapting the upper to the shape of the foot for a customised fit. Sidi’s famously reliable and replaceable closures are improved by an all new proprietary Sidi Wire material that is completely non-binding for intuitive and effortless on-the-fly adjustments. Like most Sidi small parts, the Tecno-3 Buckle is serviceable and replaceable Buy Sidi Footwear from Chain Reaction Cycles, the World's Largest Online Bike Store.