Filter King 35.5x40.5x1 Air Filter 4-Pack - MERV 8 Pleated

In this review the Filter King 35.5x40.5x1 4-pack is assessed as a straightforward, no-frills replacement filter for residential HVAC systems. The bottom line: it is a solid choice for homeowners who need a correctly sized, MERV 8 pleated filter that is fully manufactured in the United States and fits without fuss. Performance is focused on capturing everyday airborne particles while maintaining airflow, and the manufacturer notes the actual panel thickness is 0.75 in, which matters if the return grille has a tight fit.

Key Features

• MERV 8 rating: Provides effective capture of common household particles like dust and pet dander while preserving normal system airflow.
• Actual size transparency: The filter lists an actual size of 35.5 x 40.5 x 0.75 in so buyers can confirm fit for frames that expect precise dimensions.
• Pleated design: The pleats increase surface area to trap more particles and extend the usable life compared with a flat panel filter.
• Made in USA: Fully manufactured domestically under EPA establishment number 103501-FL-1, which signals local production and material control.
• Long service window: Rated to last up to 90 days with a recommended replacement interval of 30 to 90 days depending on conditions, simplifying maintenance schedules.

Who It's For

This filter is best for homeowners and renters with standard 1 in HVAC filter slots who want a balance of particle capture and airflow, such as families with pets or light indoor dust. The clear actual size and pleated construction make it a good pick when a precise fit and predictable performance are priorities.

It is less suitable for users who need medical-grade filtration or MERV 11+ performance for allergy or immunocompromised situations; those buyers should look for higher MERV ratings or specialized air cleaners. Also, if your system requires a full 1 in rigid frame rather than a 0.75 in panel, double-check fit before purchasing.

Pros & Cons

Pros

• Good balance of particle capture and airflow thanks to the MERV 8 pleated media.
• Accurate sizing information reduces the chance of ordering the wrong filter size.
• Manufactured in the USA, which appeals to buyers wanting domestic production.

Cons

• Actual thickness is 0.75 in, so it may not be ideal for systems that require a full 1 in rigid panel.

Specifications

Our Verdict

The Filter King 35.5x40.5x1 4-pack is a practical, value-minded choice for typical homes that need reliable MERV 8 filtration and correct sizing. Its pleated design and domestic manufacture make it a dependable replacement option for HVAC systems that accept a 0.75 in panel; homeowners seeking higher filtration efficiency should choose a higher MERV product.

Frequently Asked Questions

Is this filter a true 1 in thickness?
The listed actual thickness is 0.75 in, so it may sit thinner than some 1 in rigid panels; measure your frame before ordering.

How long will each filter last?
Filter King recommends replacing 1 in filters every 30 to 90 days, with these pleated filters able to last up to 90 days depending on use and environment.

Where are these filters made?
These filters are fully manufactured in the United States and include the EPA establishment number 103501-FL-1.