EZ Flex Filter Kit 20X25 Size Includes EZ-Flex Filter And 2 Reusable End Caps. EZ Flex expandable filter uses a simple, three-step assembly process that is much faster and easier than any expandable filter on the market. Other expandable filters can take up to 10-15 minutes to assemble, requiring the installation of up to five combs. Because the EZ Flex expands to the correct size without using combs, it can be assembled in less than 30 seconds. STEP#1 STEP#2 STEP#3 To complete assembly, place the second end piece across the opposite side of the filter. Simply remove the filter from its box and expand to full size. Place one of the re-usable end pieces on a flat surface and insert the expanded filter.  2002 year model and newer