It's the Nissan "First Aid Kit" that goes in the rear hatch. It has bandages, cleansing towels, tweezers, etc. You'd be better off purchasing a brand new one as they aren't that expensive. CourtesyParts.com has them for $22:
http://www.courtesyparts.com/nissan-fir ... =6833_7314&
*Note: If you don't have the straps and clips to hold the kit in, you have to order them seperately through Nissan.
The Nissan "Emergency Road kit" is a different kit and I don't think it'll fit in the rear hatch opening (it measures 13.5"x10"x5"). It runs for $56 from CourtesyParts.com and includes jumper cables, flashlight, some tools, reflective triangle, etc.:
http://www.courtesyparts.com/nissan-eme ... =6833_7314&