Excerpted rocket science:
By creating a higher airspeed in the intake path, you increase air mass and airspeed, which greatly increases horsepower. When the two different paths of air meet, they create a vacuum, which is where the airspeed starts to multiply, forcing more air into the engine at a higher rate and thus creating more horsepower.
Shorter version:
1. By creating a higher airspeed you increase airspeed.
2. Making the air go faster makes it heavier?
3. Making the air go thru a tube INSIDE a tube makes the air in both tubes go different speeds.
4. Air travelling at different speeds creates a vacuum, sucking more air into the engine?
Looks like an intake with a filter on the end.
The gibberish they quote is garbage...they leave out the added resistance of two tubes vs one, and also are pretending that the slight pressure difference created by the two tube flow is stronger than the drag required to pull it through in the first place.
If they were not insane and or stupid and or just ripping people off...it would mean that you could mount one of these on your roof, and drive a bit, and then let the vacuum created by the two different flows pull you along for free, etc.
So - if you want an open element intake with a foam filter on the end...it might act as an open element filter on an intake...which in itself is typically less restrictive than a closed airbox...
Of course, if you do get an open element filter, and you go into some water, it will be sucked into the engine, rather than the airbox with a water trap.

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- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
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