21 Divide and Conquer Kamado BBQ Grill Accessory. Kamado Universal Divide and Conquer Cooking System 21 Grill. This is for a new Divide & Conqueror system for a 21 Kamado BBQ. There are many ways to consider these sizes, this cooking grill has an inside ridge of 38.5cm and an outside ridge of 47cm. So if your Kamado ceramic core this rests on to has an insider diameter less 38.5cm you will not be able to fit this in to it, and larger than 47cm it will fall inside. Hope this helps if you are not aware if your egg is termed 21. This multifunction two-zone baking system enables cooking different dishes simultaneously at different temperatures and on different height levels! This system is a replacement for the traditional grill grate. Thanks to the semicircle “shelves” you can organise your cooking surfaces in a different way – for direct and indirect baking. The two-zone grill grates and multi-level structure provides a wide variety of cooking possibilities and makes the cooking much more simple. If you use this system, you will no longer need the heat deflector. Multifunction two-zone grilling system.