Run-flat tyres have reinforced sidewalls and are designed to keep the tyre fixed to the wheel, even when operating at low pressure. Most tyre manufacturers DO NOT recommend a Run-flat tyre be repaired following use at reduced pressure.
Extra Load tyres are an evolution of the reinforced tyre for heavier, higher performance vehicles, allowing a lower profile tyre with extra load carrying capability. These tyres give more rigidity and enhanced road holding.
Asymmetrical tyres have a different tread pattern on each side of the tyre. This allows different patterns with differing wet/dry performance characteristics to be combined in one tyre.
Mercedes recommended tyres. These tyres have been specifically designed to compliment the performance characteristics of their vehicles.