The shimano rx830 35mm carbon 700c cx rear wheel is the new road disc specific 17c tubeless wheel from shimano the rim has carbon laminate that runs all the way up the sidewall allowing to keep appropriate stiffness but whilst using thinner aluminium rim extrusion the rim is laced onto a 135mm shimano hub with a high quality sealing cup cone bearing system with centre lock disc rotor mount 140mm compatible and a 1011 speed compatible freehub available in 24h black only