The BD1631J50100AHF from TTM Technologies is a Balun with Frequency 1.6 to 3.1 GHz, Amplitude Balance ±0.15 to 1 dB, Phase Balance 2.3 to 4.8 Degree, Insertion Loss 0.6 to 1 dB, Power 2 W. Tags: Surface Mount, Balanced to Unbalanced. More details for BD1631J50100AHF can be seen below.