Looks like the ring fits where the charcoal grate would be, then the firebox fits in that which gives you some extra charcoal depth. Then you can use the griddle for cooking in, or leave the griddle off and use your normal cooking grate for searing or indirect cooking. Oh, and I think if you are searing, you can put the square plate in the charcoal bin so the coal sits at the level it would be if you were putting coals on the coal grate. It seems like this product needs a video to explain it a little better.