Sold in caulking tubes, this material is great for sealing cracks around the burner and for packing the valleys on the surface of the burner grate. It consists of ceramic fibers dispersed in a very sticky sodium silicate based refractory binder requiring only drying to produce a hard surface, low thermal conductivity insulation. It has excellent adhesion to metal surfaces and unlike asbestos products, very low shrinkage. It dries hard like furnace cement, yet unlike furnace cement is easily removed by prodding with a screwdriver. Care should be taken to prevent freezing the product before use or it will harden in the tube. Therefore we usually will not ship it during the winter months. Sold in caulking gun-sized tubes.