Smith Single-Stage 7-GPM GAC Whole House Water Filtration System. The item “A. O. Smith Single-Stage 7-GPM GAC Whole House Water Filtration System” is in sale since Wednesday, January 27, 2021. This item is in the category “Home & Garden\Home Improvement\Plumbing & Fixtures\Pumps & Water Filtration Systems\Water Filtration Systems”. The seller is “thecreativerefuge2012″ and is located in Yucca Valley, California. This item can be shipped to United States, Canada, United Kingdom, China, Mexico, Germany, Japan, France, Australia, Russian federation.