4.5x36.5x1 Air Filter 4-Pack MERV 8 - Made in USA King

In this review of the 4.5 x 36.5 x 1 air filter 4-pack, the reviewer finds a practical, no-frills replacement filter for homeowners and renters who want reliable dust control without complex installation. The biggest reason to buy is straightforward: these MERV 8 pleated filters capture more airborne particles than basic flat filters while maintaining airflow, and they are fully manufactured in the United States, which matters to buyers seeking domestic production and consistent construction.

Key Features

• MERV 8 rating: Provides effective capture of common household particles such as dust and pollen without significantly restricting airflow.
• Pleated design: The pleats increase surface area so the filter traps more particles and lasts longer between changes.
• Made in USA: Fully manufactured domestically with consistent materials and construction under EPA establishment number 103501-FL-1.
• 4-pack convenience: Supplying four filters at once makes it easier to follow the recommended 30 to 90 day replacement cycle for 1 in filters.
• Fast installation: The open, slide and close fit is simple and generally quick for most furnace and A/C filter slots.

Who It's For

Homeowners and renters with standard 1 in filter slots who want an upgrade from fiberglass flat filters will appreciate the improved dust control and longer service life; the MERV 8 rating suits households concerned about general indoor air quality but not requiring HEPA-level filtration. Those who prefer products made in the United States will also value the domestic manufacturing claim.

It is not aimed at people who need medical-grade filtration or have specific allergy or immunocompromised needs where higher MERV or HEPA filters are recommended. Also, customers with nonstandard filter dimensions should verify the actual size of 4.5 x 36.5 x 0.75 in before buying.

Pros & Cons

Pros

• Good balance of particle capture and airflow thanks to the MERV 8 pleated construction.
• Manufactured in the USA, which supports consistent build quality and supply traceability.
• Four filters per pack offer convenience and value for routine replacements.
• Many customers report improved dust control and noticeable air quality within days.

Cons

• Actual thickness is 0.75 in rather than a full 1 in, so users should confirm fit for some tight slots.
• While most find installation easy, a minority report some difficulty fitting the filter into certain frames.

Specifications

Brand	Filter King
Pack size	4-pack
Rated MERV	MERV 8
Nominal size	4.5 x 36.5 x 1 in
Actual size	4.5 x 36.5 x 0.75 in
Made in	United States (EPA Establishment 103501-FL-1)
Recommended change interval	30 to 90 days for 1 in filters

Our Verdict

The Filter King 4.5 x 36.5 x 1 MERV 8 4-pack is a sensible, value-oriented choice for most homes needing improved dust control without sacrificing airflow. With pleated media, domestic manufacture, and a convenient 4-pack, it is good value for routine replacements, provided buyers confirm the actual 0.75 in thickness fits their filter compartment.

Frequently Asked Questions

What is the actual thickness of the filter?
The actual thickness is 0.75 in, although the nominal size is listed as 1 in, so measure your slot before purchase.

How often should these filters be changed?
The manufacturer recommends changing 1 in filters every 30 to 90 days depending on use, with many users finding good performance up to 90 days.

Will these filters affect airflow?
With a MERV 8 rating and pleated design, they capture more particles while maintaining typical airflow for most residential HVAC systems.