Carlsson revised the model's exterior with a comprehensive aerodynamics package comprising of a restyled front bumper that incorporates a lip spoiler and LED fog lights. Other styling enhancements include side skirts, rear apron with a built in diffuser and a boot lid spoiler. There is also a choice of alloy wheel designs.
For the interior, Carlsson's menu includes an Alcantara sports steering wheel as well as pedals and foot rest made of brushed aluminium. Floor mats featuring the firm's logo with a matching boot cover completes the interior enhancement.
The tuning house offers performance upgrades for the CLS 350 CGI petrol and 350 CDI V6 diesel models. With the CK35 kit, the V6 petrol engine's output is lifted from 306HP and 370Nm to 333HP and 410Nm. As a result, the car's 0-100km/h sprint time drops from 6.1 seconds to 5.9 seconds. Thanks to the firm's C-Tronic DIESEL POWER electronic tune, the 350 CDI produces 320HP and 780Nm of peak torque, up from the stock model's 265HP and 650Nm. This allows the diesel-powered to go from 0 to 100km/h in 5.9 seconds instead of the standard 6.2 seconds.
Other performance upgrades include Carlsson’s patented C-Tronic Suspension system that can lower the vehicle's ride height by up to 30 mm. It can also constantly adjust the spring travel depending on the road conditions.