Whirlpool Genuine Parts: This whole home filtration system provides clean, fresh water throughout the entire house for drinking, cooking, bathing, and cleaning. Ideal for households of 1-4 persons. Replacement filter NOT included. 3/4" Inlet: Featuring stainless steel inlets that lasts longer than the plastic ones. Additional fitting adapters may be required depending on the sizes of plumbing pipes. Built-in Value: Featuring a pressure relief button, this water filtration system reduces water sputtering at faucet and provides an easy solution for filter replacement. Also replaces WHCF-DWH. NSF Tested and Certified: A water filtration system you can trust – certified by the National Sanitation Foundation International against NSF/ANSI Standard for material safety and structural integrity. For cold water use only. Optimal Maintenance: For best filtration results, it is recommended to use Whirlpool genuine replacement filters WHKF-GD05/WHSW/WHWC/WHPL. For installation, Whirlpool WHKF-B6 housing mounting bracket provides additional support.