WHOLE HOUSE WATER FILTER SYSTEM. 1ST STAGE SEDIMENT FILTER 2.5 X 20. 2ND STAGE CARBON BLOCK WATER FILTER 2.5 X 20. Slim 20″ Housing WITH Pressure Release 1/2″ IN/OUT PORT. GREAT SYSTEM FOR WHOLE HOUSE. Track Page Views With. Auctiva’s FREE Counter. The item “Big Blue Whole House Slim Dual Water Filtration System 20 Housing 1/2 Port” is in sale since Wednesday, June 22, 2016. This item is in the category “Home & Garden\Kitchen, Dining & Bar\Small Kitchen Appliances\Water Purification\Water Filters”. The seller is “dhillonnoni” and is located in Canyon Country, California. This item can be shipped to United States.