Weapon R Performance Air Intake Replacement Parts ? Weapon R Secret Weapon Replacement Air FilterWeapon R newly designed Secret Weapon Filter, which provides maximum airflow, with the protection of high quality dense Poly Urethane Foam. Many studies have shown Flow rates of up to 80% more Air and Better Dirt Filtration with Foam Filter than the conventional cotton filter. The SW1 main feature is a Computer CAD Designed and Flow benched Tested TURBO Velocity Stack, which greatly increases airflow, airspeed and air mass into the engine, therefore increasing engine performance. Another one of the SW1 Filters great features are the capability to be disassembled to be cleaned and then re-assembled after cleanings or to change the color of the foam filtering element.