The Saturn Vue Green Line is GM's first production hybrid, blending a 2.4-liter gasoline engine with a basic electric assist motor and nickel metal hydride battery pack. It includes regenerative braking to recharge the battery pack, and has an auto-stop feature to automatically shut off the gasoline engine when sitting at a traffic light or in traffic. It is a mild hybrid that cannot be driven on battery power alone. An “eco” light in the gauge cluster tells the driver when fuel economy is maximized, but the Green Line does not include an average fuel economy display or power meter like other hybrids. The Green Line is $3,225 more expensive than a Vue four-cylinder with an automatic transmission.