When you compare two parts using the Compare Geometry utility, you can see unique and modified faces between the parts. This is helpful when you compare an original part to a revised version of the part.
Click 
next to Unique faces.
Bracket_A.SLDPRT
and
Bracket_B.SLDPRT
update to show the unique faces in red.
| Bracket_A.SLDPRT
|
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| Bracket_B.SLDPRT
|
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