This is injection molding ...
Injection molding or plastic injection molding is a process for manufacturing plastic parts.
Various materials (e.g. thermoplastics and elastomers) are heated and liquified before being injected into an injection mold. Cooling in the mold causes the injection molded part to solidify again and a dimensionally stable end product is created. Plastics processing can be carried out using single-component injection molding or multi-component injection molding. This process is particularly suitable for plastic part production for large series, but injection molding can also be used for small series production of technical plastic molded parts.