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TopTech TechPure TT-FM-2025 QB OEM 20x25x4 Replacement Furnace Filter - QwikBox(R)

TopTech TT-FM-2025 20x25x4 furnace filters are designed for the TechPure TT-MAC-2522 & TT-MAC-2025 air cleaners. They are rated at MERV 11 and remove many allergens, dust, pollen and other airborne pollutants. The new QwikBox(R) collapsed design provides for less chance of shipping damage and takes up less space so it is more convenient to keep spare filters on hand. Assembly required. 

  • New QwikBox(R) Collapsed Design That Is Easy To Assemble Prior to Installation
  • MERV 11
  • TopTech TechPure OEM Original Equipment Replacement Air Filter
  • Fits TechPure TT-MAC-2522 & TT-MAC-2025 Air Cleaners
  • Actual Size 19.375" x 24.375" x 3.75"

Customer Reviews

Based on 11 reviews
Air filter

Excellent service and the best price anywhere! I won’t shop for my air filter anywhere else

Perfect OEM

Great buy on assembled filter ! I will be back!!!

Smooth Transaction

I needed a replacement filter and stumbled upon the one I needed on the Atomic Filters website when searching online. Retail stores like Home Depot don't sell this. I previously ordered one via Amazon. It arrived unassembled and the price was higher than what I paid for this one. My new filter arrived on time, assembled, and undamaged. And the price was reasonable. Nothing more I could ask for. I will continue to buy these filters through Atomic.

Furnace Filter

This was my third order of the particular filter. I chose your company because you have the original equipment filter at a price that is cheaper than what I would pay my HVAC company.

Great Fit - Fast Service

As advertised!

Just what I needed.

Will buy again.

Related Items

Nominal Vs. Actual Sizes: Finding the Right Air Filter Size

Buying the Correct Size Air Filter- The Most Important Thing to Know 

When you are buying your air filter online most important thing to know is Air Filters have two sizes that you need to understand the Nominal size and the Actual Size. Not understanding these numbers often leads to consumers purchasing a filter that does not fit their Furnace or HVAC system.

Nominal vs Actual air filter size by Atomic


Understanding Nominal Filters Size Could Save You Time and Money

Not understanding the Nominal Filter Size is the primary culprit for incorrectly purchased filters.The Nominal Size is the usually the dimensions used to Label the filter. For instance 16x20x1. These dimensions are a rounded value on the filters actual measurements. The actual measurements on this filter may be 15.5x19.5x.75, but that could vary by brand and manufacturer. So in order to make sure you have the correct size filter, especially if you are replacing with a different brand it is important to confirm the actual size on the filter. When purchasing filters on the internet the Nominal size is usually found in the product title.

Actual Filter Size- The Key to Making the Right Replacement Filter Purchase

The actual size as you might have guessed are the actual dimensions of the filter by length, width and thickness. This size is often on the filter right below the Nominal size and is usually labeled as the actual size. When you are buying a filter online the actual size is sometime in the product bullet point or the product description. If your filter does not have actual dimensions on the outside of the filter, you can measure you filter to get the correct dimensions. Some brands have a foam gasket on the outside of the filter, in this case, you will want to make sure you have a compatible actual size and that it also has the foam to ensure a snug fit. 

Lennox Air Filter X0851 with Foam strips

Examples of Nominal and Actual Sizes

 Size  Example 1  Example 2
Nominal Size 20x20x1 16x20x1
Actual Size 19.5x19.5x.75 15.75x19.75x.75


 Furnace filters should fit securely but should not have to be forced into position. If you have to force the filter into its slot, then it is probably too big. Forcing an improper filter size in a filter can cause it to buckle, damaging the filter or reducing its ability to function properly. Filters are a smaller than their slot to allow for easy replacement. Some HVAC units may need a filter with dimensions that are unique or uncommon. In these cases, a custom filter needs to be ordered.

Find Your Filter Sizes Easy in 1" Deep Filters , 2" Deep Filters, 4" Deep Filters