The Null Void Projector is a powerful weapon that is used to transfer aliens to the Null Void, a never-ending intergalactic jail (the Null Void isn't really an intergalactic prison, as seen in the episode Voided). Several of the Null Void projectors lie in the interior chamber of Mt. Rushmore. It has been gradually refined through the ages; according to Kevin, the Mk. 1 model was a large machine similar in appearance to the handgun, however it required time to recharge between intervals and could only be carried around in the trailer of an Isuzu Forward due to its aforementioned size. The most modern version is similar to the handgun one except it takes less time to charge, allowing easy access to the Null Void. It can also be overloaded when its focusing lens is removed, allowing it to be used as an impromptu bomb. It's a weapon commonly used by the Plumbers.
Ben has been into the Null Void 4 times, once in the original series, twice in AF and once in UA. The only time he went into the Null Void with the Null Void projector was in the first series in Back With a Vengeance.
Manny and Helen thought it was a disintegrator ray before Kevin told them otherwise.
The projector Manny and Helen used was a bigger version of the Null Void projector, also known as a Mark 1 or Mk I.
The Null Void projector has been coming in various sizes lately. For a while, the Null Void projector was small enough for a Human character to use. However in Perfect Day, it was big enough for Four Arms and Vilgax to use (even though that was a dream). Later, in Plumbers' Helpers, the Mk I variant appeared and the only method of transport for it was an Isuzu Forward, and Swampfire could get in and out. Finally, in Vilgax Attacks, it was almost as big as a section of Vilgax's ship.
And along with different sizes, there are also different styles that the Projector went through: in the original series, the projector was shaped and designed like a semi-automatic pistol with a trigger for the pointer finger to activate the projector. In Alien Force, the projector was designed like a hand-cannon with an icepick grip-type handle that required an individual to press a button on the top with their thumb to activate it. Due to the existence of both variations at the same time, one can assume that the S-AP variant was used exclusively for human Plumbers due to the familiarity of the handle configuration.
The version created by Caesar Salazar is named the "Dimensional Disrupter".
The idea of the Null Void Projector sending criminals to the Null Void parallels that of the Phantom Zone Projector in the world of the comic book character Superman, in which criminals are sent to the Phantom Zone.