Punch Retainers / Punch Holders Punch Retainers are mechanical components used in mold-making industries for holding the core and cavity inserts in position within a mold. They are designed to provide stability and alignment between mold components during the injection molding process. Retainers are commonly made from high-strength steel or aluminum alloys, which help prevent deformation under the high pressures of the molding process. They are an essential component in ensuring the accuracy, precision, and repeatability of the molded parts. Retainers also provide for the safe operation of the mold by securing the inserts in place, preventing any potential safety hazards that may arise from a shifting or misplaced insert during the molding process.