The E504A4 from Microwave Engineering Corporation is a 90 Degree Hybrid Coupler with Frequency 2.5 to 5.5 GHz, Average Power 800 W, Peak Power 6 kW, Isolation 21 dB, Coupling 3.3 dB. Tags: Module with Connectors, Octave Band. More details for E504A4 can be seen below.