AR RF/Microwave Instrumentations Model DC4255 is a high power, ultra-broadband coupler with excellent performance characteristics over a range of 4 decades. This Dual Directional Coupler is a convenient means of simultaneously monitoring forward and reverse power in high power systems using normal laboratory oscilloscopes, voltmeters, power meters and spectrum analyzers. The Model DC4255 is recommended for use with our A and L series amplifiers, and other amplifiers operating within the frequency and power range, and our PM2003 Power Meter.