21x21x5 Air Filter MERV 11 for Allergen Defense Replacement

The 21x21x5 air filter by Filterbuy is designed to provide superior filtration for your HVAC system. This pack of four filters is perfect for enhancing the efficiency of your furnace, air conditioner, or heat pump. With an actual size of 20.63 in x 20.63 in x 4.38 in, these filters fit seamlessly into your existing setup, ensuring optimal performance.

One of the standout features of these filters is their MERV 11 performance. This rating means they can effectively capture up to 95% of dust, allergens, and pet dander, making them an excellent choice for maintaining a healthy indoor environment. The synthetic media used in these filters is comparable to MPR 1200 and FPR 7, ensuring that you are getting top-notch filtration without compromising air flow.

Durability is another key aspect of the Filterbuy air filters. Made with electrostatically charged media, these filters trap more microscopic particles than traditional fiberglass models. With eight pleats per foot, they last three times longer than standard filters, making them a cost-effective solution for your home. It is recommended to replace them every 90 days for the best results.

Installation is a breeze with the superior construction of these filters. They feature recyclable beverage board frames with dual wire backing, which outperform basic cardboard designs. This construction not only enhances durability but also helps the filters resist extreme temperatures, ensuring they perform well in various conditions.

These filters are compatible with several models, including Rheem and Ruud filter part numbers PD540018, as well as Protech models 540012, 540018, and PD540012. Additionally, they fit housing part numbers RXFH-E21AM10 and RXFH-E21AM13, making them a versatile choice for many HVAC systems.

In summary, the Filterbuy 21x21x5 air filter is an excellent investment for anyone looking to improve their indoor air quality. With its lasting filtration capabilities, easy installation, and compatibility with various HVAC systems, it stands out as a top choice for homeowners and businesses alike. Don't compromise on air quality; choose these filters for a cleaner, healthier environment.