2015 Nismo Conversion on 2012 Base

cooltoy

Maybe a slightly better (or more clear) explanation is that, the Nismo's wing is a large piece (not just a wing) that covers the hatch below the wing and extends all the way down to the edge of the hatch.
In order to compensate for the extra thickness added to the edge of the hatch by the wing, Nissan needed to make the portion of the rear bumper, that meets the hatch, stick out a bit further in order to sit flush with the now extended hatch.
When the bumper is put on a non-Nismo without the Nismo wing, the bumper will now stick out slightly past the edge of the hatch.

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