POP TOP is a type of bottle or can closure. It is made up of three parts: a TAB, which is a small metal lever that is used to open the container; a CAP, which is a plastic or metal lid that fits over the opening of the container; and a SCREWCAP, which is a metal or plastic CAP that screws onto the container to secure it. Together, these three components form a POP TOP closure, which is used to keep beverages and other liquids fresh and secure.