The BD3150N50100A00 from Anaren Inc is a Balun with Frequency 3.1 to 5 GHz, Amplitude Balance ± 1.3 dB, Phase Balance 7 Degree, Insertion Loss 0.7 dB, Power 1 W. Tags: Surface Mount, Unbalanced to Balanced. More details for BD3150N50100A00 can be seen below.