TECHNOLOGY – Maximum 25,000 BTU Patented DUAL FUEL TECHNOLOGY Operates off Natural Gas or Liquid Propane Which Heats up to 1,100 sq. ft. Area. DEPENDABLE – Thermostat Control – The control automatically cycles the burner on and off to maintain a desired room temperature STYLISH – 5 improved realistic looking logs With Space saving design without sacrificing beauty ECONOMICAL – 99. 9% efficient with Vent Free gas burner. No outside duct or chimney needed! Environmental Protection and Energy Conservation. SAFE – Battery assisted Piezo ignition with Built-in oxygen depletion sensor (ODS) immediately shuts down the heater if carbon monoxide or lack of oxygen is detected.