Our pan burners are constructed from high-quality tube burners covered in a bed of sand. The logs rest on a sturdy 5/8 wrought iron grate above the sand and ember bed. Gas percolates up through the sand and burns beneath the logs. The triple burner creates massive flames properly proportioned between the front and rear of your fireplaces. Includes Triple Burner, 5/8 inch Grate, Embers, Lava Rock, Crushed Glass, Flex Line and Fittings. Features Model # AVR21MTEKN. Fuel Type Natural Gas. BURNER ONLY Millivolt Triple Burner. UL Certified. Two main tube burners. Smaller front ember bed burner. Burners ship assembled for Natural Gas, LP Conversion Kits available. For use with LA21 and LTH1118 by Empire Comfort System. Specifications Overall Dimensions 21 L . BTUs 75,000. Required Must Choose Log Set to Complete This Unit Not Included, Sold Separately 21-inch Advantage 7 Piece Refractory Log Set LA21 . 18-inch Tree House 11 Refractory 11 Piece Log Set LTH1118 .