Sitting directly above your Bull BBQ main burners is a pyramid-shaped stainless steel piece of stainless, these are referred to as flame tamers In the past Bull BBQ, flame tamers were a solid piece of stainless steel and did not feature any holes on top of the unit. Recently, Cal Poly took a Bull BBQ and set out to create the most versatile, and reliable cooking surface, what they came up with was the Bull BBQ ReliaBull heat technology. The various, differently shaped holes on the top of the flame tamer allow for proper airflow and heat to go directly through the tamer, and not around (like the old model). This creates a 70% less cold spot on your Bull BBQ grill. The Bull BBQ (16631) replacement Reli-A-Bull flame tamers are constructed of durable 304-grade stainless steel, distribute heat, minimize grilling flare-up and fit all Bull BBQ gas grills (any model). To install, simply remove current worn-out flame tamers by pulling them directly out of the grill and replace with new. Installation takes less than 1 minute. Bull BBQ's new Reli-A-Bull technology was created to eliminate uneven heating on your grill, making your outdoor grilling experience extraordinary. This new technology improves heat distribution on your grill by 50%. The Bull BBQ Reli-A-Bull flame tamers create a more even grilling surface, eliminating hot and cold spots, so that you can use your entire grilling surface.