Update your semi with clean and dry pneumatic systems to optimize air brake performance, with the OTR AD-9 Style Air Dryer Cartridge with Expertise Built In™. This replacement air dryer filament removes oil, dust, dirt and contaminants from the air lines to prevent corrosion, ice formation, and potential valve damage. Engineered with rugged materials to endure demanding operating conditions such as rough vibrations and high temperatures. FleetPride is your First Click in Heavy Duty®.