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Cast Iron
Newer cars have standard cast iron brake disks, the Sport 135, Sport 190 and 111S using cross drilled versions. These have a better ability to handle the heat generated with hard track use than the MMC disks. The downside is that much more brake dust is generated but, Halfords sell a brilliant product called Wonder Wheels which is amazing at removing brake dust and always returns my alloys to spotless condition.

Ащще занимательно.