Several major automakers unveiled concept cars at auto shows in 2009 that previewed new designs and technologies. General Motors showed the Chevrolet Volt electric car concept that could travel up to 40 miles on battery power alone. Ford revealed the C-MAX Hybrid concept featuring a plug-in hybrid powertrain and interior design focused on maximizing cargo space. Concept cars allow automakers to test new styling ideas and engineering concepts before committing to production vehicles.