Furnace Filters

20x20x5
16x20x5
Tried these two but they are too cheap, missing the foam line on the bottom to make a good seal
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2
These were better
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The 2 pack above was sold out, here is a 3 pack
Trying these:
link At the time of writing this had 2x 16x20x5 and 20x20x5 MERV 13 as two options $35 per filter.
See if MERV 13 makes a noticable difference.