Craycort Preseasoned Cast Iron Cooking Grates for Spirit 210 and Genesis A Gas Grills (Set of 2) Cast Iron gives off a more even heat and holds it far longer than steel - great for amazing grill marks/sears Seasoned Cast Iron Grates provide a non stick cooking surface - brush the grate clean in seconds Strong & resilient - Cast Iron Grates withstand higher temperatures than normal grates. And like other good Cast Iron product it will last a lifetime if cared for properly Our grates are thicker, have more rods and are heavier than most other grates out there.