3M Filtrete has several types of "1" disposable air filters available. Below are the 4 types of filters available.

BEST: Filtrete Advanced Allergen Filter (1500 / Blue)
3M Filtrete high performance Advanced Allergen Filters filters carry a microparticle rating of 1500 and capture small and large particles including smoke, smog and particles that carry viruses. They also meet the American Lung Association ® indoor air quality guidelines. These offer the highest performance for Filtrete "1" filters.

BETTER: Filtrete Ultra Allergen Filter (1250 / Purple)
3M Filtrete High Performance "1" filters capture at least 90% of large airborne particles from the air passing through the filter. They outperform all non-electrostatic filters including three-month pleated, washable and fiberglass "1" filters. Filtrete high performance filters carry a microparticle rating of 1200 or higher and capture small and large particles including smoke, smog and particles that carry viruses. They also meet the American Lung Association ® indoor air quality guidelines.

GOOD: Filtrete Micro Allergen Filter (1000 / Red)
3M Filtrete Air Cleaning "1" filters outperform all non-electrostatic (three-month pleated, washable and fiberglass "1") filters. These filters carry a microparticle performance rating range of 700 - 1000. They attract and capture microscopic allergens like dust, smoke, and smog particles and large allergens like mold spores and pet dander.

FAIR: Filtrete Dust & Pollen Filter (600 / Light Blue)
3M Filtrete High Airflow "1" filters effectively capture larger particles from the air. These filters attract and capture household dust and are ideal for high-velocity equipment. A Filtrete filter with a microparticle rating range of 200 - 600 is ideal for people who want to help reduce larger particles such as household dust, pollen, mold spores, and pet dander from the air passing through the filter. These filters are also suitable when you have an air conditioner running.