The PDC2 from Astatic is a dual readout multifunction meter. In addition to SWR and power, the included antenna allows you to measure field strength around your CB antenna. This is useful for finding dead zones in the radiation pattern of your antenna. The meter measures 5 5/8" W x 2 3/8" T x 2 1/2" D, including the antenna connections and calibration knob.
Please note that installing this device in the antenna line requires an extra CB coax jumper to go from the device to your radio.
If you need more information on setting up your antenna, please see our article on how to tune a cb antenna.