3M Filtrete Allergen Defense Air Filter

MPR stands for Microparticle Performance Rating. A rating of 1000 indicates that this filter is effective at capturing large particles like dust and lint, as well as smaller micro-allergens like pollen, pet dander, and smoke, making it a solid upgrade from basic fiberglass filters.

This filter is designed for systems that accommodate a 4-inch thick filter. Because it is 4 inches deep, it will not fit in systems designed for standard 1-inch filters, so please check your current filter housing dimensions before purchasing.

No, this is a disposable synthetic filter. It is designed to be replaced rather than cleaned, as washing it would damage the filtration media and significantly reduce its ability to trap particles.

While 4-inch filters generally last longer than thinner versions, you should check your filter every 3 to 6 months. Environmental factors like pets, smoking, or high dust levels in your home may require you to replace it sooner to maintain optimal airflow.

Because this is a 4-inch deep filter, it actually provides more surface area than a 1-inch filter. This increased surface area allows for effective particle capture without significantly restricting airflow, provided your HVAC system is compatible with this thickness.