An Arburg 270M also known as a plastic injection molding machine. Plastic pellets would be dumped into the yellow hopper where they would fall into a heated barrel, melt, and then be compressed by a piston and injected into a pre-fabricated mold. Once cooled the hardened plastic would be popped out of the mold and be used to create the actual aluminum piece. Below is a video detailing an Arburg 270M in action.