Custom-Sized AAF Flanders PrePleat Air Filter – MERV 13 (M13) Efficiency

Description

This is our custom-size AAF Flanders PREpleat M13 air filter, delivering MERV 13 filtration built to your exact dimensions. When your HVAC system has a non-standard filter opening — common in older homes, commercial rooftop units, and legacy air handlers — stock nominal sizes leave gaps that let unfiltered air bypass the filter. Custom sizing closes that gap so your system actually filters the air it handles.

When a custom size is the right call

• Legacy air handlers with non-standard filter openings
• Commercial rooftop units with manufacturer-specific filter slots
• Older residential returns that don’t match today’s nominal sizes
• Replacement for a filter you’ve been trimming or stacking to fit
• Built-in filter housings where the equipment was designed around the filter

How to order

Measure your existing filter (not the housing it sits in — filters are typically slightly smaller than the housing for installation clearance) to the nearest 1/8 inch in length, width, and depth. If you’re unsure about measurements or which filter spec is right for your system, contact us with a photo of your existing filter or housing and we’ll confirm before production. Our Filter Fit Guarantee means if you measure wrong, we’ll remake the filter at no additional cost.

What MERV 13 captures

Very fine particles including smoke, bacteria-sized particles, and virus carriers attached to larger droplets, on top of everything MERV 11 captures. Commonly specified for commercial spaces with higher indoor-air-quality requirements and for homes with wildfire smoke or air-quality concerns. Ensure your HVAC system is rated for the increased static pressure.

Construction

• Media: Progressive-density bi-component synthetic fibers. Mechanical capture — performance does not fade as the filter ages.
• Frame: Moisture-resistant beverage-board with diagonal support members and expanded-metal media support bonded to the downstream side.
• Max operating temperature: 180°F (82°C)
• Sizing tolerance: Built to 1/8 inch increments

Typical applications

Commercial office, light institutional, and residential HVAC where MERV 13 is specified — including facilities responding to wildfire smoke or higher indoor-air-quality requirements. Confirm the HVAC system is rated for the increased static pressure.

Also worth considering

Shopping on price? Our house brand PrimeShield Elite (MERV 13) covers the same efficiency tier across common residential and commercial sizes and is usually the better value. Choose this branded option when your equipment spec sheet or facilities team calls for it specifically.

Questions on fit, quantity, or a commercial quote?

Need a size that isn’t listed, a different pack count, or a quote for a commercial order? Get in touch — we handle facilities and commercial orders daily and can usually match or beat distributor pricing.

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