The 2009 Mercedes-Benz SL-Class is a two-seat roadster with a retractable hardtop. Standard features on the SL550 include 18-inch wheels; an active suspension system; active bi-xenon headlamps; a wind deflector; heated wipers and washer nozzles; rain-sensing wipers; auto-locking interior storage bins; dual-zone automatic climate control (with sensors that detect sun position, roof and window position, humidity/dew point and the number of vehicle occupants); power tilt/telescoping steering wheel; 12-way heated power front seats with memory; leather upholstery; Bluetooth; Mercedes-Benzs COMAND electronics interface; a navigation system; and a Harmon Kardon Logic7 surround-sound stereo with six-CD/DVD changer, iPod integration, SD memory card reader and an in-car hard drive for digital music storage. The Mercedes-Benz SL-Class comes standard with stability and traction control, antilock brakes with brake assist, side head/thorax airbags, driver knee airbag and a pop-up roll bar that deploys automatically in the event of a rollover. It can also be raised by the driver at the touch of a button. TeleAid emergency telematics are also standard, including automatic collision notification.