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The Lennox X6670 is the OEM standard for many residential media cabinets, including the Honeywell FC100A1037 and F100/F150 series. With a MERV 11 rating, it captures 65% of particles in the 1–3 micron range—fine dust, smoke, and most allergens—while keeping static pressure low enough for a standard 1/2 HP blower motor. The actual dimensions measure 24.75 x 15.75 x 4.38 inches, so it slides into the cabinet with a snug fit that prevents unfiltered bypass air.

The pleated paper construction is reinforced with a lightweight beverage-board frame that resists warping in humid basements. At just 1.4 pounds, it’s notably lighter than multi-pack options, but the single-carton packaging means you’re buying exactly what you need without storing spares.

Durability across a full 90-day to 6-month replacement cycle is excellent—the pleats hold their shape without collapsing, and the media does not shed fibers into the airstream. For homeowners with a Lennox or compatible Honeywell cabinet who want a MERV 11 sweet spot without moving to aftermarket brands, this is the reference standard.

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The Filterbuy 20x25x5 2-pack delivers MERV 8 filtration with a dual wire backing that gives the frame serious rigidity compared to cardboard-only designs. The actual dimensions are 19.88 x 24.75 x 4.38 inches—a tight tolerance that fits most media cabinets without gaps. The electrostatic synthetic media is charged during manufacturing to attract particles, and the 8 pleats per foot provide enough surface area to last the full 90-day recommended cycle.

What sets this pack apart is the build quality for the mid-range price point. Each filter weighs 7.5 pounds thanks to the wire mesh reinforcement and plastic/polypropylene framing, which means it won’t sag or deform even in high-humidity furnace rooms. Compatibility spans Honeywell F100/F200, Carrier, Bryant, Lennox X6673, and Payne systems, making it one of the most versatile options for residential media cabinets.

One common buyer note is that the shipping packaging can be inconsistent—some units arrive in a cardboard box, others in thin plastic wrap that can bend a corner. The filter itself performs well for dust and pollen reduction, and users with pets report noticeable improvement in airborne dander within days. If your cabinet accepts a 20x25x5 nominal filter and you want a reliable MERV 8 at a fair per-unit cost, this 2-pack is the volume purchase to beat.

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The AIRx Filters 20x25x5 2-pack offers a budget-friendly entry point into 5-inch media replacement, specifically targeting compatibility with Lennox X6673, X0586, and HCF20-10 cabinets. The actual dimensions are 19.75 x 24.75 x 4.38 inches—slightly tighter in width than the Filterbuy option, which can be helpful in cabinets that need a precise fit to avoid rattling. The MERV 8 rating handles pollen, dust mites, and mold spores with the standard 8 pleats per foot.

Construction uses a fiberglass and paper media sandwiched in a lightweight frame. At under 4 pounds per filter, it’s easy to slide in and out, though the frame feels less substantial than metal-reinforced alternatives. Users report that the filters fit their Lennox cabinets perfectly and perform well for basic residential dust control. The value proposition is straightforward: you get two MERV 8 filters at a cost that undercuts many single-pack OEM options.

Where this filter falls short is media density—the pleats are not as tightly packed as the Filterbuy or Filtrete options, which means the dirt-holding capacity is lower and you may need to replace closer to the 90-day mark rather than stretching to 6 months. For a seasonal home or a system that sees light use, this is a solid choice. For year-round full-time HVAC operation, the slightly higher initial cost of a premium MERV 8 2-pack will pay off in longer filter life.

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The Lennox 19L16 steps up to MERV 13 filtration, capturing 50% of particles in the 0.3–1 micron range—bacteria, smoke, and fine combustion particles. This is the highest MERV rating in the lineup and is appropriate for homes with severe allergies, smokers, or anyone living in wildfire-prone areas. The polyester pleated media is denser than paper-based alternatives, which means higher static pressure, but the 5-inch depth provides enough surface area to keep the pressure drop manageable for most residential blowers.

The actual dimensions match the 16 x 25 x 5 inch nominal size closely, and the polyester material resists moisture better than paper, making it a good choice for basement installations or humid climates. At 2.16 pounds, it’s heavier than standard MERV 8 filters, reflecting the denser media pack. Owners consistently report that this filter lasts a full year in their Lennox Healthy Climate cabinet before needing replacement, which reduces the per-year cost significantly compared to cheaper filters swapped quarterly.

The critical trade-off: not every HVAC system can handle MERV 13 without airflow issues. Several buyers note that their service technician recommended stepping down from MERV 16 to MERV 13 to reduce blower strain. If you have a variable-speed blower or a newer system, MERV 13 is usually safe. For older single-speed units, measure your static pressure drop before committing to MERV 13 long-term.

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Filtrete’s 20x25x5 filter uses the company’s proprietary 3-in-1 technology that electrostatically charges the media to pull in particles like a magnet. With a MPR (Microparticle Performance Rating) of 700—roughly equivalent to MERV 8—it captures 70% of large particles including dust, pollen, and pet dander. The actual dimensions are 19.56 x 24.13 x 4.75 inches, which is notably thicker than the standard 4.38-inch media, giving it the largest pleat depth in this comparison.

This filter is specifically designed to fit Trion Air Bear, Bryant, Carrier, and Totaline media cabinets, not Lennox or Honeywell systems. The 4.75-inch thickness means it occupies the full depth of the cabinet slot, maximizing media surface area and dirt-holding capacity. The included Filtrete Smart App integration lets you set 90-, 180-, or 365-day reminders, which is helpful given that this filter is rated for annual replacement rather than 90-day swaps.

The overall build quality is excellent—the frame holds its shape, the pleats are evenly spaced, and the electrostatic charge is active from the moment you open the seal. Some buyers switching from Air Bear brand filters note that the Filtrete feels equally sturdy and performs identically at a lower per-unit cost. The main limitation is compatibility: the 4.75-inch thickness may not fit shallower media cabinets, and the MERV 8/MPR 700 rating is not sufficient for households needing allergy-grade sub-micron filtration.

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The Trion Air Bear 255649-105 is the OEM replacement for Air Bear brand media cabinets, featuring pleated cotton construction that differs from the paper/polyester blend used by most competitors. The actual dimensions are exactly 25 x 16 x 5 inches—matching the nominal size precisely, which is unusual in this category. The filter frame has integrated fingers that hold the vertical pleats evenly spaced, maximizing dirt-holding capacity across the entire media surface.

The electrostatic synthetic material is charged to attract and hold particles without relying on a dense media pack that would restrict airflow. This allows the filter to maintain MERV 8 efficiency with lower static pressure than paper-based filters of the same rating. The cotton material also has natural moisture resistance, reducing the risk of mold growth in damp conditions. Users consistently report that these filters last a full year between replacements while keeping dust levels noticeably lower.

The main drawback is compatibility: Trion explicitly states this filter is NOT a direct replacement for Lennox or Honeywell filters. It’s built for Air Bear, Bryant, Carrier, and Totaline cabinets only. The per-unit cost is higher than the equivalent MERV 8 from Filterbuy or AIRx, but the precise fit and pleat spacing technology justify the premium for Air Bear owners who want a guaranteed seal without measuring gaps.

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The Lennox X6670 OEM 2-pack delivers two genuine MERV 11 filters with actual dimensions of 15.65 x 24.65 x 4.31 inches—noticeably smaller than the nominal 16x25x5, but engineered to fit the specific slot dimensions of Lennox HCF16-10 and HCC16-28 cabinets precisely. The MERV 11 media is rated for 98% efficiency at capturing particles as small as 0.3 microns, using a dense polyester pleated material that doesn’t shed fibers into the airstream.

The build quality reflects true OEM manufacturing: the frame is rigid, the pleats are uniformly spaced, and the media tension is consistent across the entire surface. At 0.01 ounces per filter (the stated shipping weight appears to be in error—actual handling weight is closer to 2 pounds each), these are light but sturdy. Users who have ordered these for years report that the fit is exactly what their Lennox system requires, with no gaps or bypass issues.

The value equation here is about confidence: you pay a premium for the Lennox name and the guarantee that the filter will fit and perform as designed. The 2-pack is particularly useful for owners with multiple Lennox units or for those who want to buy in bulk without worrying about third-party sizing variations. If your system is a Lennox Healthy Climate or HCF-series media cabinet and you want to maintain the factory-prescribed balance between filtration and airflow, this 2-pack eliminates all guesswork.