8890-300 Series, RF Loads are self-contained high-power 50 ohm coaxial transmission line terminations requiring no outside power source or additional equipment. It provides accurate, dependable, and practically non-reflective termination for testing and adjusting transmitters under non-radiating conditions. The load consists essentially of a cylindrical film type resistor immersed in a dielectric coolant. The resistor, individually selected for its accuracy, is enclosed in a special tapered housing which provides a linear reduction in surge impedance directly proportional to the distance along the resistor.