The X4C45K1-02S from TTM Technologies is a Directional Coupler with Frequency 3.6 to 5.1 GHz, Coupling 1.9 dB, Coupling Variation ±0.35 dB, Average Power 10 W, Insertion Loss 0.2 dB. Tags: Surface Mount. More details for X4C45K1-02S can be seen below.