A rubber sucker is a device that is used as a sticking device in place of glue for a short period of time.
A rubber sucker is a device used in suction clams, toys, sunlight blockers – suction cups, and a variety of other applications where temporary sticking is required but glue is not preferred.
When a rubber sucker is pressed against a wall or any other surface, it squeezes the air so that the atmospheric pressure outside the sucker holds it firmly against the surface.