Contamination is a dirty word. You want to stay clear of it. But the fact of the matter is that various parts on your aircraft, including brakes, are exposed to contamination in the form of dust, grease, oil and a whole host of other nasties. Blast them all away with 3M's 051135-08180 High Power Brake Cleaner.
For more information, read the Product Data Sheet as well as the MSDS.
NOTE: This item is not for sale in California