A jet nozzle diffuser
is a type of airflow control device used in heating, ventilation, and air conditioning (HVAC) systems. The diffuser consists of a round opening which is connected to an air supply duct or an air handling unit. The primary purpose of a jet nozzle diffuser is to provide a long throw of air, meaning that it can project air over a relatively large distance from the diffuser outlet. Jet nozzle diffusers are often used in large commercial and industrial space such as airports, auditoriums, sports center and shopping malls.