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.
Mercedes recommended tyres. These tyres have been specifically designed to compliment the performance characteristics of their vehicles.