The Magnetic Flux Beam is a Proton Pack and Particle Thrower invented by Professor Dweeb designed to capture ghosts. It is notably much larger in size that the equipment used by the Ghostbusters and Extreme Ghostbusters.
On a third consecutive attempt to catch Slimer, Professor Dweeb planned to blast and confine Slimer with the Magnetic Flux Beam and Elizabeth would activate the accompanying trap. However, the Squid Ghost retaliated and slimed the pair before the trap could be used. Dweeb dropped the Magnetic Flux Beam in the Firehouse as he was blasted. Slimer later fired the beam at the Squid Ghost to help keep it confined as Winston Zeddemore threw out a Trap.