18 Inch Palmetto Oak 5-Piece Log Set & NG Millivolt Control Burner Features: Vent-Free. Five Piece Log Set. Includes Millivolt Control Burner. Piezo Ignitor. Oxygen Depletion Sensor. Natural Gas Specs: Rating: 25,000 / 36,000 Btu/hr. Gas Type: Natural. Ignition: Piezo. Manifold Pressure: 3.5″ w.c.. Inlet Supply Pressure (inches of water): Maximum – 10.5″ w.c., 5″ w.c.. Minimum Fireplace Clearance to Combustible Materials: -Side Wall: 16″ -Ceiling: 42″ -Front: 36″ Minimum Required Hearth Area Dimensions to Fit This Log Set: -Front Width: 24″ -Height: 17″ -Depth: 13.5″ -Rear Width 20.5″ A licensed gas technician is required for installation of this product. Please check your local regulations as some areas may require inspection after installation of gas products. It is highly recommended that you use your own gas technician or gas provider for any repairs. Residential Warranty: Parts – 4 Years. Note: Required GLS202-24 Flex Connector Installation kit.