Revolutionary ultrasonic technology is used to create the flame and smoke effect of the Dimplex OptiMyst II Insert. As the mist rises up through the logs, the light reflects against the water molecules creating a convincing illusion of flames and smoke. The result is an appearance so authentic it will be mistaken for a true wood-burning fireplace. Purchased for our new conversion but we have now changes the layout so unable to use - gutted as it looks amazing.