S&B cold air intake part number 75-5047 for 2003 to 2007 5.9L Dodge Cummins.  This intake offers an astonishing 50.6% increase in airflow over the stock intake, and maintains a 99.81% efficiency rating at 653 CFM when running a cleanable filter. The dry filter showed a 49.6% increase in airflow while remaining 99.68% efficient at 653 CFM. When its cool out, remove the included plug from the secondary box opening, and engulf an insane amount of air. With the secondary port open, the restriction of the air flow is decreased. Lower restriction equals better airflow. We offer intakes with two types of filters: Cotton (cleanable) or Dry (disposable). Since you are not sacrificing performance with either choice, the decision comes down to would you rather throw away the filter or clean it. The part numbers for intakes with a dry filter end with 'D'.