Custom-Sized Fiberglass Panel Air Filter – MERV 1–4, Disposable Basic Option

Description

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.

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