Mercedes-Benz SL Operator's Manual page 605

Wheel and tire combinations
603
Winter tires are not available at the factory
as standard equipment or optional extras.
If you want to equip your vehicle with
approved winter tires, it may be necessary
to obtain wheel rims in the corresponding
size. The size of the approved winter tires
may differ from the standard tires. This is
dependent on the model and the
equipment installed at the factory.
The tires and wheel rims, as well as further
information, can be obtained at a qualified
specialist workshop.
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