The C5 was described as "the baby of the family".[2] The C10 was intended to be a city car, capable of carrying two passengers at up to 40 miles per hour (64 km/h) in a roofed but open-sided compartment with two wheels at the front and one at the back. Wood Rogers intended it to effectively be an updated version of the Isetta, a 1960s Italian microcar. Sinclair built a full-scale mock-up of it; according to Wood Rogers, "it looked great.