cabin filter question

[Guju Rider]

I recently "recharged" my K&N intake filter and went a head and did the cabin filter as well. I was installing it in the tray and then wondered if it mattered which way the filter was inserted. The factory Nissan cabin filter had a direction for air flow when I removed it and then charcoal one didn't have any direction. Now the 3rd one (charcoal) I'm replacing does have a directional air flow. The 2nd one that didn't have an arrow of which way the air should go, and worked fine, I didn't experience any problems. Does it matter which way the filter is inserted based on the air flow pattern? Or are the ridges on the filter the same no matter what way you put it in?

[audtatious]

I believe the arrow should point down. If the filter is directional you will want it facing the proper direction.

[Guju Rider]

i thought since the flow of air would be from bottom to top and out the cents..so i have the arrow facing up even though all the writing and stuff is upside down...

http://www.youtube.com/watch?v=K9ZmVT3ryiY

that video shows that the first filter writing was upside down (I couldnt see which was the arrow was..but when he put in the new one..the arrow shows bottom to top...)

[audtatious]

Might be different for the '07+. I know I can see the filter from the engine compartment near the battery which would make my direction "down".