Front caliper PN differences ? - 26292CA002 vs 26292CA021
 

Found 3 different part number sets that seem to be for 13-15 BRZs with a 294mm vented front rotor.

26292CA002 is the one listed on parts.subaru.com (front right), but I've seen other places that list other calipers for the cars.

Is 26292CA002 - the standard caliper (supersedes CA000/CA001) ?
What is different about 26292CA021 - ?
Is 26292CA041 - the same but red ?

Similar for left side (CA012/CA031/CA051).

Is the last digit the revision number? So the 002 would have some update that the 021/041 do not have?

Thanks.