For those that remember me recommending the HP2009 as it had a bypass valve in the top of the canister only to discover when I cut one open that is was in the bottom I have a new discovery. Before cutting open the old/used filter I ordered a replacement as a spare which has been sitting on the shelf, today I opened up the box to look at the filter ( for no apparent reason ) only to discover that this K&N HP 2009 has the bypass at the top
The only reason I can put this down to is the one with the bypass at the bottom was made in Mexico but the one with the bypass valve at the top ( the new one ) was made in Korea. Now I am thinking the the spec varies depending where it made.

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