Christopher, there are a few brands of that stuff, but probably the most widely used is called Kaowool. Here's a link to anvilfire, a supplier. I've ordered kaowool from them before. They have good service, and they even sent me a little extra anvilfire Store : Blacksmithing books, Video tapes, CD's, Refractories and anvilfire gear. buy the 1" thick material. Two layers is sufficient, but the more the better.