Filter King 17.5x21.5x1 Air Filter 4-Pack - MERV 8 Pleated Filters

In this review the Filter King 17.5x21.5x1 Air Filter 4-Pack is judged on fit, filtration and value. It is best for homeowners and renters who need a mid-range MERV 8 replacement that balances particle capture with airflow; the single biggest reason to consider it is the pleated design that traps more dust and airborne debris without noticeably restricting system performance. The pack of four and the claim of up to 90 days of use make it a practical choice for routine HVAC maintenance.

Key Features

• MERV 8 rating: Provides effective capture of common airborne particles while maintaining good airflow for most residential systems.
• Actual size: Measures 17.5 in x 21.5 in x 0.75 in so it fits housings sized for nominal 1 in filters when true dimensions are needed.
• Pleated construction: The pleats increase surface area to collect more dust and extend usable life between changes.
• Made in USA: Fully manufactured in the United States with EPA establishment identification for traceability and quality control.
• 4-pack value: Four filters in one purchase simplifies scheduled changes and reduces the per-filter cost compared with buying singly.
• Easy installation: The simple open, slide and close design makes filter replacement quick and straightforward for most users.

Who It's For

This set is aimed at homeowners, renters and small business owners who want reliable, mid-level filtration for A/C and furnace systems and who change 1 in filters on a regular schedule. It suits anyone looking for a straightforward upgrade from very basic fiberglass filters without the added restriction of higher-MERV pleats that can tax older fan motors.

It is less appropriate for those needing high-efficiency allergy or medical-grade filtration, and households that require HEPA-like capture should look for higher MERV ratings or supplemental filtration devices. Also measure your filter slot carefully: a few reviewers noted width variation, so exact fit matters.

Pros & Cons

Pros

• Good balance of particle capture and airflow thanks to the MERV 8 pleated media.
• Four-pack provides convenience and lower cost per replacement.
• Made in the USA with consistent build quality and clear manufacturing identification.
• Easy to install with a simple slide-in design that most homeowners manage quickly.

Cons

• Actual thickness is 0.75 in which may cause a tight fit in some frames expecting exactly 1 in filters.
• A few customers reported mixed impressions on long-term durability compared with heavier-duty models.

Specifications

Brand	Filter King
Nominal size	17.5 in x 21.5 in x 1 in
Actual size	17.5 in x 21.5 in x 0.75 in
MERV rating	MERV 8
Quantity	4-pack
Country of manufacture	Made in USA (EPA 103501-FL-1)
Recommended change interval	30 - 90 days

Our Verdict

The Filter King 17.5x21.5x1 4-Pack is a sensible, good-value choice for routine residential HVAC maintenance: it captures dust effectively, is easy to install and is fully made in the USA. For most households seeking improved indoor air quality without putting strain on older systems, this pack is practical and cost-effective, though those needing tighter tolerances or higher efficiency should consider other options.

Frequently Asked Questions

How often should these filters be replaced?
Filter King recommends replacing 1 in filters every 30 - 90 days depending on use and household conditions.

Will a MERV 8 filter restrict airflow?
MERV 8 balances filtration and airflow; it captures common particles without significantly impacting most residential A/C or furnace performance.

Are these filters really made in the USA?
Yes, the product is fully manufactured in the United States and lists an EPA establishment number for reference.