Custom Size MERV 1-4 Fiberglass Disposable Panel Air Filter

Name: Custom Size MERV 1-4 Fiberglass Disposable Panel Air Filter
Brand: RTF
SKU: C-10055-01
Price: 199.99 USD
Availability: InStock
Rating: 4.866666667 (15 reviews)

$ 199.99

Shipping calculated at checkout.

Custom Size

Please provide the exact dimensions you would like us to make your filters. For example, you could specify 18-1/4 x 23-7/8 x 1.

C-10055-01

Size Restrictions

Minimum Size: 6" x 6" x 1"

Maximum Size: 27" x 36" x 1"

Need a filter larger in length or width? Reach out to our support team for help!

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What is a MERV rating?

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Please note: The image shown may not reflect the actual size of the filter. Refer to product specifications for accurate dimensions.

This is our custom-size MERV 1-4 fiberglass disposable panel filter — built to your exact dimensions in any size. For HVAC equipment protection and maximum airflow where stock nominal sizes don't fit your filter opening.

Understanding the MERV 1–4 rating

Fiberglass media is rated MERV 1 when clean and builds up to MERV 4 as dust loads onto the fibers. That's not inconsistency — it's how spun-glass media works. A fresh filter lets the most air through while still blocking larger debris; as dust collects, the media becomes more efficient at catching finer particles. The goal of a MERV 1–4 filter isn't air quality — it's equipment protection with maximum airflow. It keeps lint, hair, and large dust out of your coil and blower, which is exactly what older systems, high-airflow applications, and pre-filter duty need.

When a custom panel makes sense

Legacy commercial air handlers with non-standard filter slots
Older residential returns that don't match today's nominal sizes
Workshop and garage ventilation systems
Pre-filter duty in multi-stage systems with non-standard housings

How to order

Measure to the nearest 1/8 inch. Our Filter Fit Guarantee covers measurement errors at no cost. Contact us for help.

Construction

Media: Continuous-filament spun fiberglass with resinous bonding
Frame: One-piece moisture-resistant chipboard
Service life: 30 days under typical use
Sizing tolerance: 1/8 inch increments

Also worth considering

Shopping on price? Our house brand PrimeShield MAX Airflow (MERV 1–4) 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.

Specifications

MERV Rating	MERV 1-4
Filter Media	Spun Fiberglass
Filter Support Grid	No media retainer
Frame	1-piece heavy chipboard
Removes	MERV 4 rated filters are a great choice if you need high airflow and to protect your HVAC system. Removes larger particles like dust and lint.
Life	Recommended 30 day changeout
Quantity	12 Filters
Part Number	#VALUE!

MERV	Captures	Efficiency	Airflow Impact	Replace Every	Shop
MERV 1–4	Lint, dust, pollen, carpet fibers, some pet hair	Up to 20% of 3.0+ micron particles	Minimal — maximum airflow	1–3 months	Shop →
MERV 8	Adds mold spores, dust mite debris, pet dander, hair spray	Up to 75% of 3.0–10 micron particles	Low	1–3 months (1″), 6–12 months (4″+)	Shop →
MERV 10	Adds finer dust, most airborne household particles	Up to 85% of 1.0–3.0 micron particles	Low–moderate	1–3 months (1″), 6–12 months (4″+)	Shop →
MERV 11	Adds fine pet dander, auto emissions, some airborne bacteria carriers	Up to 90% of 1.0–3.0 micron particles	Moderate	2–3 months (1″), 6–12 months (4″+)	Shop →
MERV 13	Adds smoke particles, fine allergens, many virus carriers	Up to 90% of 1.0–3.0 micron, up to 75% of 0.3–1.0 micron	Higher — verify system compatibility	2–3 months (1″), 6–12 months (4″+)	Shop →

MERV	FPR (Home Depot)	MPR (3M Filtrete)	Performance Summary	Shop
MERV 1–4	FPR 1–3	MPR 100–200	Basic equipment protection. Minimal airflow resistance.	Shop →
MERV 8	FPR 5–6	MPR 600–800	Mold spores, dust mites, pet dander. Residential standard.	Shop →
MERV 10	FPR 7	MPR 1000–1200	Fine dust, hair spray, fabric fibers.	Shop →
MERV 11	FPR 8	MPR 1200–1500	Pet dander, fine allergens, auto emissions.	Shop →
MERV 13	FPR 10	MPR 1900–2200	Wildfire smoke, fine allergens, many virus carriers.	Shop →

Custom Size MERV 1-4 Fiberglass Disposable Panel Air Filter

$ 199.99

Filter Reviews

Any questions?

Find answers to common questions on filters, sizing preferences, MERV ratings, order status updates, and more in our helpful FAQ page. Visit FAQ Page

General

How often should I replace my HVAC filter?

Most pleated filters should be changed every 90 days. However, households with pets, allergies, or heavy HVAC use may need to replace filters every 30–60 days. Commercial and industrial sites may require more frequent changes based on conditions.

Do you offer custom sizes?

Yes! If you need a filter with an exact size—down to the 1/8 inch—we can help. Visit our Custom Size Filters page to get started.

What if the filter doesn’t fit right?

We’ve got you covered with our Filter Fit Guarantee. If the size doesn’t fit your system as expected, reach out to our support team and we’ll make it right.

What makes you different from big box stores or other filter sites?

We’ve been online for nearly 20 years, and our team has over 50 years of combined HVAC experience. We sell American-made filters from trusted brands like AAF Flanders and Koch Filter—no cheap knockoffs or low-performance imports. We’re also a proud NAFA member, which means we’re committed to real air quality expertise and professional standards.

Do you sell the same filters used in commercial or government buildings?

Yes. In fact, we supply filters to schools, clinics, and government agencies nationwide. Many of our filters—especially MERV 10, 11, and 13—meet or exceed specifications for professional use. You’re getting professional-grade protection for your home.

Are your filters certified or tested?

Yes. Almost all of our filters meet or exceed ASHRAE standards and are manufactured under strict quality control. Many are used in hospitals, schools, and government facilities—so you can trust they perform as advertised.

How do I know what size filter I need?

Look for the size printed on your old filter or measure the filter slot in your system. We recommend rounding up to the nearest 1/8” for custom sizes. You can also visit our How to Measure Filters page for step-by-step help.

Do you offer bulk discounts or commercial pricing?

Absolutely. If you’re ordering for a business, property, or large facility, we’ll provide a quote and recommend the right products for your needs. Reach out to our Commercial Services team anytime.

What is MERV?

What is a MERV rating and why does it matter?

MERV (Minimum Efficiency Reporting Value) rates how well a filter captures airborne particles. The higher the MERV rating (typically 1–13 for residential use), the finer the particles it can trap—from dust and pollen to bacteria and smoke. We offer filters from MERV 1–13 to match your system’s needs and your air quality goals. Learn More

Will a higher MERV rating restrict airflow?

Filters with higher MERV ratings are denser and can reduce airflow in systems not designed for them. MERV 8–10 is a safe choice for most homes. For MERV 11 or 13, ensure your system can handle the increased resistance or contact our team—we’re happy to help you choose the right balance of efficiency and airflow.

Will using a high-MERV filter damage my HVAC system?

Not when matched properly. All of our filters are designed for low pressure drop and optimal airflow. If you’re unsure, contact us—we’ll help you choose a filter that your system can handle safely.

Do higher MERV filters improve indoor air quality?

Yes. Filters with higher MERV ratings (10–13) trap smaller and more harmful particles like mold spores, smoke, bacteria, and allergens. They’re ideal for families, people with asthma or sensitivities, and anyone wanting cleaner, healthier air inside.