In place of wool, we add natural graphite powder to the latex of our Vegan Mattress. The graphite acts as a naturally-derived fire retardant barrier and exceeds all U.S. standards for flammability. Graphite powder is commonly called expandable graphite. When it comes into contact with fire, the graphite expands super fast and absorbs the oxygen. Of course, for anything to burn, you need oxygen. So this process prevents burning, and it does not release any toxins, either. Few, if any, other companies use this technology because the graphite can get stuck in machinery. Because we own and operate our factories, we can make latex with graphite powder in small batches.