The Panamera is offered in three versions, the rear-wheel drive S, the all-wheel drive 4S, and the all-wheel drive Turbo. Each come with a direct injection 4.8-liter V-8, the S models making 400-hp, while the Turbo adds twin-turbocharging for 500-hp. The Porsche PDK double-clutch gearbox is the only transmission choice, and all models are equipped an auto start-stop feature for increased urban fuel economy. The body appears to be a four-door sedan but with a coupe-like profile and a power liftgate rather than a typical trunk for access to the spacious luggage area. Standard safety features include ten airbags, bi-xenon adaptive headlights with LED daytime running lights, rain sensing wipers, full LED rear lighting, four belt pretensioners and electronic traction and stability control. A small sample of optional tech features include Bluetooth, rearview camera, electronic logbook, Burmester high-end audio system, twin-screen rear entertainment system, voice activation, servotronic steering, active anti-roll bars and ceramic composite brakes.The Panamera is now the fifth model line offered by Porsche.