Mercedes-Benz SLK-Class 2008 Owner's Manual page 255

Technical data
Tyres and wheels
Spare wheel*
Depending on the country, the engine and the wheels fitted, your vehicle may be equipped with TIREFIT or a collapsible emergency spare
wheel*.
i
Vehicles with MOExtended tyres (tyres with run-flat characteristics) are not equipped with the TIREFIT kit by the factory.
Collapsible emergency
41
spare wheel*
41 Use of snow chains not permitted.
252
All models, except SLK 55 AMG Performance Package
Tyres 145 / 70 - 17 92P
Tyre pressure 3.5 bar
Wheels 4.5B x 17 H2 ET 12
* optional