Maximum Heat Is Delivered By The Upper Tier Burner For More Rapid Boils And Hotter Sears. The Low Flame On The Lower Tier Burner Eliminates The Need For A Double Boiler Completely, And Keeps Even Delicate Sauces Warm Without Fear Of Scorching Or Separating. Ensure Safer Cooking As Each Burner Has A Sensor To Detect If A Flame Has Gone Out. If So, It Automatically Re-Ignites, Maintaining Temperature Control. Maintain Control With Four Dual-Stacked BurnersMaintain Control With Four Dual-Stacked Burners That Go From 20,000 Btu Down To A Mere Breath Of Flame Simmer And Melt SaucesSimmer And Melt Sauces, Soups, And Marinades Easily With The Lower Tier Of The Dual-Stacked Burner Reignites Flame AutomaticallyReignites Flame Automatically With Spark Ignition System Move Pots And Pans - Cast IronMove Pots And Pans Effortlessly Across The Continuous Cast-Iron Grates Cleanup Is A Snap - Burner PansCleanup Is A Snap As Sealed, Seamless Burner Pans Contain Sloshes And Spills Match Other Products With Heavy-Gauge Stainless SteelMatch Other Sub-Zero, Wolf, And Cove Products With Heavy-Gauge Stainless Steel And Signature Red Infinite Control Knobs Rangetop Specifications(Ul)(Li)Stainless-Steel Island Trim (Included)(/Li)(Li)Stainless-Steel Bezels(/Li)(Li)1 - 9,200 Btu Burner(/Li)(Li)1 - 15,000 Btu Burner(/Li)(Li)1 - 18,000 Btu Burner(/Li)(Li)1 - 20,000 Btu Burner(/Li)(/Ul)