The second generation of the Mercedes-Benz CL-Class is the C215-chassis coupé of 1998–2006. It was considered by Mercedes as their premier model. It is based on the 1998–2005 Mercedes-Benz S-Class (W220), though it rides on an shorter wheelbase. Construction of the chassis was a unibody type unique to the CL Class, constructed of a steel floor pan, chassis rails and A pillars. With a bonded aluminium roof and rear wing sections, magnesium door frames and composite plastic used for the boot/trunk and front wings. Sales in Germany started in August 1999 for the CL 500 V8. The C215 exterior design and active suspension was previewed by the Mercedes-Benz F200 concept in 1996. The CL-Class was offered as seven models: the naturally aspirated V8 powered CL 500, the naturally aspirated V8 powered CL 55 AMG, the supercharged V8 powered CL 55 AMG Kompressor, the naturally aspirated V12 powered CL 600, the naturally aspirated V12 powered CL 63 AMG, and the Bi-Turbo V12 powered CL 600 Bi-Turbo and CL 65 AMG Bi-Turbo. All models seat four. Exterior design produced a for regular models and 0.29 for AMG. Features and equipment The CL-Class coupés came equipped with the very latest in Mercedes-Benz technology, and along with the S-Class sedans the CL coupés receive new technological features. C215 was the second car (after the W220 S-Class) with Distronic: the first worldwide radar-assisted Autonomous cruise control system. It was the first car in the world with both low beam and high beam (Bi-Xenon) High Intensity Discharge headlamps. The C215 was standard equipped with hydropneumatic suspension, the Active Body Control or ABC system. It is technically more advanced than standard Airmatic air suspension found on the W220 S-Class sibling, and keeps the car level even in fast corners, provides a comfort and sports setting. Also, the car height can be increased by using a button, increasing ground clearance (3 settings) for driving on difficult terrain, lowers automatically at higher speeds. From 1999 through 2003, the V12-equipped cars featured a cylinder deactivation system called Active Cylinder Control. The feature was dropped when the bi-turbo V12 was introduced. This disactivation feature allowed the CL 600 to get better fuel economy than the comparable CL 500 (when not equipped with ACC itself, an option for the V8), especially on the road where the six-cylinder operation could be effectively used. Essentially, the engine is two Mercedes six-cylinder series engines mated