Hearth Sense VF18NA Vent-Free Set Gas Log, 20.5 x 14 x 10.5 inches, Brown 30,000 BTU Heats up to 1,200 sq. ft. Operates off Natural Gas Only Millivolt Control Included (Manual On/Off) 7 hand painted realistic looking concrete logs Safety Assurance: O.D.S. (Oxygen Depletion Sensor) included with automatic shut-off