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Hold off on purchasing these, we are trying to put a deal together so they come with the headers

Once again, the 5th Gen VFR air box has 2 intake paths for a very good reason: from idle to about 7,000 RPM the rubber snorkel provides a level of airflow which causes the air box achieve a resonate frequency in that RPM range. When the air box hits a resonate frequency it boosts intake efficiency, which boosts torque in that rev range. After about 7,000 RPM the 5th Gen air box opens up the flapper. This changes the resonate frequency equation, moving the air box resonance point to the upper end of the engine's rev-range. Also, the 5th Gen VFR's rubber snorkel intake is long, which is exactly what you want for the lower end of an engine's RPM range. The Flapper side of the air box intake is short, which is exactly what you want for the upper end of an engine's RPM range. As others have pointed out, the 5th Gen air box acted in a similar way to the VTEC system in the later generations of the VFR (this also explains why the dual-path air box was dropped in the VTEC versions).