When it comes to getting the most out of your Vented Gas Fireplace set, Pleasant Hearth Vermiculite provides many features of a wood-burning fire that cannot be achieved from a gas log set alone. Vermiculite helps spread gas throughout the entire burner pan for a more even & full flame pattern and well fueled fire. Pleasant Hearth Vermiculite doubles as an ash bed. Pair with Lava Rock for enhanced look! Made in the USA. 1 Year.. See full description for further details