Product Description Vermiculite Helps spread gas throughout the burner pan for a more even flame Lava Rock Increased ambient effect to your gas log set Glowing Ember Provides the same effect of a glowing bed of ashes in a wood burning fire Liquid Propane Conversion Safety Pilot Kit Allows the use of Liquid Propane as a fuel type VMC100 LVR100 GEF100 For Use With SPK100 Willow Oak Series r Dual Burner System provides two rows of flames for a more full looking fire.