Profile: R & R Communications, Inc. specializes in the sales & service of citizens band radio equipment, marine radio, radar detectors, scanners, antennas and accessories. The safety waring systems(SWS} & radar detectors detects encoded signals from a SWS transmitter and provides digital voice & text messages for highway construction / maintenance, travel/convenience information and emergency slow moving vehicles. It includes 58 digital voice and text messages. Ranger™ F390 frequency counter is a digital frequency counter. It features 6 digita continous readout and 8 to 13.6V DC operation. It works on all radios.