This is a one-of-a-kind outdoor fire feature. A natural stone boulder is hand-carved, chiseled, and core drilled. Included in the boulder kit are a natural gas fire burner, flex line, key valve, and lava rock. Propane conversion kits and electrical ignition burner systems are also available. Sizes available: Small (10″ hole with 6″ stainless burner, approx 575-800 lbs); Large (16″ hole with 12″ stainless burner, approx 800-1700 lbs); Extra Large (22″ hole with 18″ stainless burner, approx 1200-2000 lbs); Jumbo (28″ hole with 24″ stainless burner, in excess 2000 lbs).