What is a pollen filter?

Can you please oblige by explaining the importance of pollen filters? My garage has charged me £94 for replacing one installed in 2010. The car is a 2004 Mercedes 350S.
The pollen filter is the filter between the outside air and the cabin. If it gets blocked by dirt (or pollen) then the flow of air into the car will be substantially reduced.
Answered by Honest John on

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