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Your drawing is correct.


"Bi-Directional"

Reversible carbon filters exist. I did a google search. I came up with the ProFilter Reversible Carbon Filter - 50.

"
Most can-type air filters utilize 50% of the carbon available by only filtering the top section of the carbon filter, leaving the bottom part unused. PROfilter uses an innovative patented design allowing the user to reverse the filter, benefiting from the use of 100% of the carbon available and directly extending the unit's lifespan.

Manufactured with the finest TC940 virgin 3mm grain sized carbon, PROfilter effectively removes 99.5% of odors. Rated for continuous worry-free operation, PROfilter can be used for commercial or residential applications.
Requires choice of flange."