Ai Sorachi shows how to install the DCI Guns Air Brake Unit to lessen the sound signature of your AEG. They installed the unit in a CAT electric gun, modifying the gears to a 13-tooth MAP sector gear and swapping the motor for a G&G 18k motor to prevent piston clash. The presenter explains that while the air brake reduces the muzzle report, it also lowers the initial velocity to around 88.8 m/s.