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Deep Air Filters
Deep Air Filters: 3, 5 and 6-Inch
Shop 3, 5 and 6-inch replacement air filters. Check the size printed on your current filter, then choose the matching size and MERV rating.
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3-Inch Air Filters
16x25x3
Koch replacement filter for Trion Air Bear air cleaners.
5-Inch Air Filters
20x20x5
Koch replacement filters for Trion Air Bear air cleaners.
20x25x5
Return grille and furnace sizes
Looking for a 5-inch filter for a return grille or furnace cabinet? See our Practical Pleat line.
6-Inch Air Filters
24x24x6
Koch Multi-Pleat 6-inch filters.
12x24x6
Koch Multi-Pleat 6-inch filter.
20x25x6
Koch Space-Gard 6-inch filters.
Need a Different Deep Filter Size?
Call or text (954) 588-7774 with the size printed on your filter, or request a custom quote.
Standard thickness instead? Shop all 1, 2 and 4-inch sizes. Not sure which MERV rating fits? Read the MERV rating guide.
Deep Air Filter FAQs
What is a deep air filter?
A deep air filter is 3 inches thick or more. Common thicknesses are 3, 4, 5 and 6 inches. They fit cabinets and air cleaners built for that depth.
How do I know which deep filter I need?
Use the size printed on the edge of your current filter. If it is missing, measure the filter itself (width, height and thickness) and round each to the nearest whole inch. Thickness must match your cabinet.
Can I use a thinner filter in a deep filter cabinet?
Not without a proper adapter or frame. A filter that does not fill the slot lets air go around it. Order the thickness your system was built for.
What if my deep filter size is not listed?
Call or text (954) 588-7774 or use the custom filter page to send your measurements.
