The 7-series continues its tradition as BMW's flagship luxury sedan. The bold exterior styling of the last two generations has proven popular with customers. The wide range of powertrains in the 7-Series include the 740i/740Li powered by a 3.0l inline six-cylinder, the 750i/750Li powered by a 400-bhp V8, and the 760Li with its 6.0l V12. The range also includes a gas/electric hybrid model. Models with an L in the name designate long wheelbase models which add extra-back seat room. This large, heavy car is a technological tour-de-force that includes the complex iDrive system, which centralizes navigation, HVAC and audio system controls. Like most BMW models, the 7-Series is offered with a large number of packages and customization options which allow buyers to tailor the 7-Series to their tastes. In the US, BMW also imports a tuned version of the 7-Series, manufactured by Alpina. Alpina models are built on the same assembly line as the normal production 7-Series models but include a more powerful 500-bhp 4.4l V8.