Co-extrusion is a manufacturing process that involves simultaneously extruding two or more materials through a single die to create a composite product. This technique allows for the combination of different materials, such as plastics or metals, to achieve specific properties, like improved strength or flexibility. The co-extruded products often have distinct layers, each serving a unique function. For example, in the case of plastic films, one layer may provide barrier properties while another offers durability. This method is widely used in industries like packaging, automotive, and construction to enhance product performance and reduce costs.