Many common products, such as cell phones and headlights, have invisible protective vents (sometimes called protective vents) inside. The vents are made of a durable, versatile material called PTFE or polytetrafluoroethylene.
In the field of film production, "blow molding" and "casting" are two of the more commonly used processes. The following is a brief introduction and comparison of the two most commonly used production processes in film production.
