The Napoleon Heat Diffuser is made of quality stainless steel and comes with a Charcoal Ring and Heat Diffuser Plate.
The Ring is placed on top of the charcoal grate and holds the charcoal together to give a consistent heat and a longer burn time. The holes on the side keep the air flow consistent. The Heat Diffuser Plate sits on top of the Charcoal Ring to reduce the airflow to the fuel in order to burn slower and longer. It also creates a barrier with the food to create an indirect cooking zone.