As you can see here the white S-15 here has the type S areo option. That is stock from the Japanese Nissan motor company. That I beleive is the Nismo bumper. I am not sure but the only difference is the for lights are gone and the holes are opened up more.
http://community.webshots.com/user/silviasichigo use this link to view the full size version of the S-15. in Cars of japan <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt='

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