The carpet is a thin layer of compressed material, which sits on the top of the die surface. As the material goes into the pellet mill, it gets pulled beneath the roller and forms a carpet. As more material is placed in the wood pellet machine, it will be then added to the carpet. The bottom of the carpet is then forced through the die holes, as the process continues, then results in a pellet. So before the material becomes a pellet, it must be able to form a carpet.