Dimplex DFI400LH Opti-Myst Electric Cassette with Logs provides a unique alternative insert (with logs) for your indoor fireplace needs. With its revolutionary ultrasonic technology, the Dimplex Opti-Myst can create convincing flame and smoke effects while offering a more flexible installation than a standard fireplace. The Electric Cassette can be connected to a water supply for continuous use or simply use the integrated water reservoir that can ensure operation for 14-17 hours straight. The cracking sound of real flames and the multi-function remote control help finish off a unit that offers an extremely realistic fireplace experience. The result is so convincing it can often be mistaken for a true wood-burning fireplace!