The X4C40J1-20G from TTM Technologies is a Directional Coupler with Frequency 3.3 to 5 GHz, Coupling 20 to 20.2 dB, Coupling Variation ±1.5 dB, Frequency Sensitivity ±0.1 to ±0.4 dB, Directivity 18 dB. Tags: Surface Mount. More details for X4C40J1-20G can be seen below.