Filter for use with: Whole House Sediment Filter (AO-WH-PREV or AO-WH-PRE). Use only certified, genuine A. O. Smith replacement filters for continued contaminant removal and system performance. Longer lasting appliances - whole house filter system designed to reduce sediment from every tap. 35 micron filtration - reduces sediment smaller than the human eye can see. Replacements made easy - no plumber necessary. Replace filter every 3 months. Standard capacity (2.5") filter is perfect for household sizes of 1-4 people. Includes 2-pack of replacement sediment filters.