Clean and green, this Bloc 67 Ounce Ethanol Burner Insert from Bio-Blaze is ideal for those who are renovating or building a new home and want to include a fireplace that does not require a flue. Primarily designed to be integrated into an existing fireplace, this insert can simply be placed on the surface of an old fireplace in place of wood. And because it uses bio-ethanol, a clean burning fuel, the Bloc 67 oz Insert will let you enjoy all the perks of an open flame without worrying about smoke, soot or toxins. After all, although its fire burns as bright as that of a fire burning hearth, it only releases the same amount of carbon dioxide and water vapor as that of a single candle.