3M Aqua-Pure Whole House Sanitary Quick Change Water Filter System AP904. Great system, Ordered one extra unit and forgot to return it in time, Factory sealed and unopened. I use it at my house and it made a significant improvement in water taste as well eliminating buildup of gunk in the faucet aerators in the house. The item “3M Aqua-Pure Whole House Sanitary Quick Change Water Filter System AP904″ is in sale since Wednesday, October 30, 2019. This item is in the category “Home & Garden\Kitchen, Dining & Bar\Small Kitchen Appliances\Water Purification\Water Filters”. The seller is “sebstiankc” and is located in Overland Park, Kansas. This item can be shipped to United States.