Heavy-duty, reversible cast iron grates. Top grates are adjustable multi-level. Units include lava briquettes standard. Adjustable, stainless steel legs standard. The lava rocks absorb and retain the heat from the gas flame and distribute it to any areas that lava rocks are placed. This creates a more widespread cooking area and will catch and hold drippings, which enhances the delicious smells by creating more flavorful smoke and flare-ups.