- Step Down Diffusers Go by Many Names
- Lay-In, Cone Diffuser or Even T-Bar Diffusers
- The Term T-Bar Comes from the Shape of the Railing that Holds the Ceiling Tiles in a Drop Ceiling
- The Railing Forms a Grid of Square and T-Bar Diffusers are Designed to Fit or Lay-In, Those Grid Square
- The Cone Shape of the Diffuser Allows for a Maximum Volume of Airflow into the Air-Conditioned Space