The RFXF2553 from MiniRF is a Balun with Frequency 1 to 350 MHz, Amplitude Balance ± 0.2 to 0.5 dB, Phase Balance 2 to 5 Degree, Insertion Loss Less than 1 dB, Power 2 W. Tags: Surface Mount, Unbalanced to Balanced. More details for RFXF2553 can be seen below.