AEM Induction air bypass valves are designed for use with cold air induction kits to virtually eliminate the chance of water ingestion, should the filter element become wet from deep puddles, rain, or snow. They install along the upper portion of the inlet pipe on the same axis as the throttle body centerline. If there's a drop in pressure, the AEM Induction air bypass valves shut down induction at the filter and re-route incoming air through their external orifices.
This is a replacement filter assembly for the water-bypass filters included with the NISMO R-Tune Long-Tube Intake for the 370Z.
Please note that these cannot be used in forced induction applications.