Cactus Jack Filter Stone / Heat Baffle SystemRevolutionary Way To Even Your Cooking Temperatures NOW DISCOUNTED, WE HAVE REPLACED THIS WITH A STEEL PLATE SYSTEM, CLICK HERE Features Even out your cooking temperatures Eliminate hot & cool spots Improved fuel efficiency Filters ash from entering the cook chamber Helps with bark and smoke ring formation This filter stone was designed for the 16'' Cactus Jack offset smoker models. We found due to their smaller volume cook chambers they benefited