The Opti-myst® uses revolutionary ultrasonic technology to create a lifelike flame and smoke effect. The result is an appearance so authentic it will be mistaken for a traditional wood-burning fireplace.  It's not gas. It's water! As mist rises up through the media bed, light reflects against the water molecules creating a convincing illusion of flames and smoke. Each unit comes equipped with an easy to fill water tank which offers 12 to 14 hours of continuous operation before refilling.   100% safe with cool flames and no emissions. The perfect way to have a worry-free 360° flame experience