KN 33-2370, I have KN's in all my vehicles.  This one is for a 2012 Camry and I'm sure it will fit the 2011 and perhaps the 2013.  In installing these in Toyotas you will see a cotton/carbon mesh filter that is not removable in the top of the airbox.  Its a post filter and I believe it has something to do with emissions on the newer Toyotas.  You can't remove this filter, nor should you.  Buy installing the KN filter you will eliminate the large cotton/paper filter in the bottom of the tray that is removable.  This filter is a denso brand filter typically, and is very restrictive.  When you get the KN you will notice that its not quite as tall as the OE filter and thats normal so don't be alarmed.After the installation, your computer will need to re learn itself and it may take as many as three key starts for it to understand that its now getting a bit more air.  I'd say within three days you would notice and improvement.  Some have noticed improvement immediately.  Most drivers with a tuned ear, will also here their engine become a bit more agressive sounding, this to is normal and will not cause damage.If your not running a flow through exhaust such as Borla or Flowmaster, the feeling of &#34;more power&#34; will not be as much due to the flow of air not being exhausted more freely.  However you are gaining more air on the intake side which is fine on its own.  You may also pick up some fuel mileage by installing the KN.  How much mileage varies on driving conditions and how you drive your vehicle.  When it comes time to clean the filter use kit 99-5000.  Clean the filter first as instructed, then allow it to dry fully, then oil it.  DO NOT over oil the filter- follow the directions.  If handled and cleaned properly these filters can go probably longer than the life of the car.  The filter by design allows more air to get introduced into the engine, and by its use of cotton and light oil, it captures more and smaller dirt particles that a typical filter would.  If you live in dusty conditions you will need to clean the filter more often than if its street use only.  These filters will not void your warranty and will help extend the life of your car.