The Conveyor Belt Planet was one of the many planets conquered by the Irken Empire, but was liberated and restored to its former state when the Irken Republic was created and Zim laid claim to the throne as the next Almighty Tallest. The planet was at one time home to a race of short yellow creatures with screws in their heads, but was used by the Irkens as an intergalactic shipping hub (similar to the humans' FedEx and United Postal Service), sending packages to Irkens and other aliens all over the universe. The Screwheads were slaves to the Irken Empire (before Tallest ZIM liberated them under his rule), put to work labeling and shipping packages under the watchful eyes of slave drivers. If any Screwhead refuses to obey, they are met with a shock from the slave drivers' shock spears. Smikka Smikka Smoodoo, a Screwhead who was angry at what had become of his homeworld, attempted to start a revolution here, by switching the names on two packages containing a megadoomer and a set of dysfunctional SIR units respectively, which set off a chain of events that lead to the Meekrob War. He was promptly shocked into submission by a nearby guard, but was then helped back up by the same guard after he noticed that he was hurt.
The Conveyor Belt Planet was covered in numerous conveyor belts, hence the name, and is still surrounded by four circular satellites which are giant wormholes for teleportation. The actual surface of the planet is never seen, however, and may have been hollowed out in the past to make way for the conveyor belts by the Planetary Conversion Team. However, their land was reformed when Tallest ZIM ascended the throne with his empress.