The R4B offers a carefully crafted blend of comfort and light weight, fit, power transfer and aerodynamic efficiency. R4B?s single Boa IP1-A closure control is light, fast, secure, aerodynamic and comfortable ? and is complemented by a pair of light, neatly adjustable micro-straps. The R4B?s injected carbon fiber outsole is stiff for power transfer and sculpted to aid aerodynamics. It combines with the proven supportive and comfortable fi?zi:k Cycling Insole with sculpted foot-beds and supportive heel to ensure that every precious watt goes straight into your pedals. The R4B?s Microfiber upper is hard-wearing, light, and resilient with enough flexibility to ensure comfort for every rider?s foot, but strong enough to withstand the demands of racing ? without any weight penalty. The diamond-shaped laser-cut perforations help temperature management. R4B Uomo weighs just 254g (size 42.5).
