This Filtrete air filter has a lifespan of 12 months and comes in a pack of 4. It is a flat panel type with a MERV rating that can be found in the details section. The filter media is also disclosed in the details section. This 20" X 25" X 4" air filter is designed for furnace applications and has allergen reduction capabilities. The color is white and the model and filtration technology can be found in the details section as well. MPR (Microparticle Performance Rating): 1500 Designed for whole-house air cleaners within heating and cooling systems that accommodate 4" filte Particles Captured: Dust mite debris, Pet dander, Dust, Lint, Mold spores, Particles carrying viru Lasts up to 12 months.