Easton ec90 sl disc rear road wheel tubular disc brakes are the future of road cycling theyre proven in mountain and cyclocross and with the new ec90 sl disc wheels combined to the latest brake systems there are no longer anycompromises associated with going disc the ec90 sl takes the proven fantom rim shape and scales it down to a shallower 38 millimeter depth these wheels offer fierce acceleration smooth dependable durability and impressive aerodynamics from the spring classics to r