The 1600BL15B100 from Johanson Technology is a Balun with Frequency 1.5 to 1.7 GHz, Amplitude Balance 2.0 dB, Phase Balance 10 Degree, Insertion Loss 1.0 dB, Power 3 W. Tags: Ceramic, Surface Mount, Unbalanced to Balanced. More details for 1600BL15B100 can be seen below.