Mercedes-Benz SL Roadster 2012 Owner's Manual page 620

Technical data
All models (except AMG vehicles)
Collapsible emergency spare wheel
Tyres
175/55 - 18 95 P
Tyre pressure: 350 kPa (3.5 bar/51 psi)
AMG vehicles
Collapsible emergency spare wheel
Tyres
175/50 - 19 97 P
Tyre pressure: 350 kPa (3.5 bar/51 psi)
Emergency spare wheel
Light-alloy wheels
6.0 B x 18 H2 ET 25
Light-alloy wheels
6.5 B x 19 H2 ET 14
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