Caliper can rust, rotors would rust on the very first rain storm or car wash. If the paint somehow chipped off the caliper, it would definitely rust. I can't imagine anyone confusing a "caliper" with a "rotor"

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An unwavering defender of those I see worth protecting.

"promote the general welfare, not provide the general welfare"

We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.