The BD2130J5050AHF from Anaren Inc is a Balun with Frequency 2.1 to 3 GHz, Amplitude Balance ± 1 dB, Phase Balance 5 Degree, Insertion Loss 1.2 dB, Power 2 W. Tags: Surface Mount, Unbalanced to Balanced. More details for BD2130J5050AHF can be seen below.