Structural foam molding is a process of low pressure injection molding where an inert gas is inserted in melted polymer for decreasing weight and density of the finished product. In the process, however, the strength of the product is increased as well. This is actually an economical process of molding where the tooling and the equipments used are of low cost. This procedure is beneficial for the mass production of multiple of large parts of one machine in a single cycle at a much lower cost. It is a less expensive process than conventional injection molding.