The SLK350 has a 3.5-liter V6 rated at 268 horsepower. A six-speed manual transmission comes standard, while a seven-speed automatic is optional. Leather upholstery comes standard, along with a nine-speaker sound system with an in-dash CD player, an antitheft alarm and Tele Aid telematics, which provides emergency response service or direct connection to the nearest Mercedes dealer. Safety features include six airbags: frontal and side-impact bags, and small bags that protect the knees. Active safety features such as ABS with brake assist come standard along with an electronic stability program.For 2006, Mercedes broadens the SLK's appeal with the introduction of the SLK280.