Dimplex 40-Inch Opti-myst® Built-in Electric Fireplace Cassette (CDFI1000-PRO) Picture the perfect fireplace: any length, any location, and any number of sides. Forget about venting, gas lines, and hot glass, because they are a thing of the past. Now imagine flames made of water that you can reach out and touch. The revolutionary Opti-Myst by Dimplex reinvents the electric fireplace and makes it easier than ever to add a dramatic fire feature to any space. See-through, three-sided, open concept