The Lochinvar & A.O. Smith 100217961 40" Diptube Diffuser Kit is an OEM replacement component designed for compatible residential water heaters. It installs at the cold-water inlet and directs incoming water toward the bottom of the tank, helping minimize temperature mixing and improve heat distribution. This diptube diffuser kit is used in compatible Lochinvar and A.O. Smith water he... https://www.partshnc.com/100217961-lochinvar-ao-smith-34-x3-x40-diff-diptube