Sinclair C5 Isetta, a 1960s Italian microcar. Sinclair built a full-scale mock-up of it; according to Wood Rogers, "it looked great. I specified open sides to keep the cost down and having no doors meant it escaped a lot of regulations too." The design is strikingly similar to the modern Renault Twizy electric vehicle; Wood Rogers comments that "you could put the C10 into production today and it would still look contemporary." At the time of the C5's launch, Sinclair described the C15 as having "a futuristic design with an elongated 'tear-drop' shape, a lightweight body made of self-coloured polypropylene and a
Sinclair C5 a snow- and ice-covered hill – later prompted criticism even from Sinclair executives, who admitted off the record that spring conditions might have been better for a vehicle with so little protection from the British climate. The "Financial Times" called it "the worst possible timing to launch what was proclaimed to be a serious, road-going vehicle". Sinclair's biographer Rodney Dale describes it as "a calculated (or miscalculated) risk", pointing out that production was already underway, details were beginning to leak out to the press and "the launch could hardly have been held up until the possibility of a bright spring