The Prius is Toyotas gasoline-electric hybrid vehicle and was the first mass-produced gasoline/electric hybrid when it went on sale in 1997 in Japan. The Prius went on sale in the U.S. in 2000 and the second-generation Prius debuts as a 2004 model. The second-generation Prius offers distinctive aerodynamic styling and a longer wheelbase for additional interior room. The 2004 Prius is the first use of the new high-voltage/high-power Hybrid Synergy Drive, full hybrid system and will achieve a combined mpg rating in the mid-50s.