3 Pack 20x25 Replacement Filters Designed to Fit with PremierOne Pure Flo MS-2025 P6100 Cleaner Frame Size 20x25x1 Actual Filtef Szie 18.5"x22.5" Straw added for the power head / supply Manufactured in the USA ensuring quality and reliable performance. Replace Every 1 to 4 Months: Depending Local air quality for optimal performance. VALUE PACK: Includes 3 replacement filter pads in each package for extended use and convenience 3 Pack 20x25 Replacement Filters Designed to Fit with PremierOne Pure Flo Flo P6100 Cleaner Frame Size 20x25x1