NOVA STARLINK’s tight-head plastic drum is sealed at the top and bottom. They have a closed head, meaning that there’s no removable lid at either end. Tight-head plastic drums are therefore completely sealed, aside from two designated openings that are used to funnel liquids in or out. These small openings are themselves sealed with secure bungs.
Because they’re sealed, tight-head drums are often thought to be more secure than open-head plastic drums.