The BMW E63/E64 6 Series is the chassis designation for the second generation BMW 6 Series. The BMW E63/E64 replaced the BMW E24 6 Series 14 years after production had ended, whilst adding a convertible to the lineup. The BMW E63/E64 6 Series uses a shortened chassis from the BMW E60 5 Series (which formed the fifth generation BMW 5 Series), and shares similar functions including the BMW iDrive. The BMW E63/E64 6 Series' design was based on the BMW Z9 Concept, whose exterior was redesigned by Adrian Van Hooydonk, whilst David Carp designed the interior of the car. The BMW E63/E64 6 Series was introduced in autumn of 2003 in the Frankfurt Auto Show, and premiered in the North American Auto Show.