The video by Prime Mech Airsoft showcases their custom-built 2J MK18 Next Gen Build, which is based on the M4A1 CQBR SOPMOD Block II platform. This airsoft rifle utilizes the Tokyo Marui Next Gen Recoil Shock (NGRS) system, and its performance has been enhanced with several upgrades, including the installation of a Leviathan NGRS electronic control unit, PandoRA Retro Arms gears, and a Brushless T238 motor, resulting in a muzzle energy of 1.9 Joules when firing a 0.36g BB.