bbq factory Fire Glass with Fireplace Glass and Fire Pit Glass, 10-Pound, 1/4-Inch(T 6mm), grey This is 100% tempered fire glass, T 6.0mm, N.G.: 10 lbs (4.5kgs) This glass has been tested and will not melt or discolor, if properly installed and used Replaces gas logs and lava rocks Easy installation Quality inspected to ensure impeccable performance and elegant appearance