This product, which distinguishes all Savinelli pipes, is a filter system based on the properties of balsa wood. Its characteristic is the absorption, in a natural way and without additives or chemical materials, of humidity and of the annoying drizzle that is created inside the pipe barrel. It also ensures less fouling and therefore greater cleaning. This absorption power derives from the numerous porous fibers of the balsa which guarantee a perfect smoke without altering the fragrance and aroma of the tobacco. The balsa in question is 9mm therefore suitable for pipes of this diameter.