The DB-B1B25A-3G50V/H44-H4 from Rosnol is a DC Block with Frequency DC to 3 GHz, Insertion Loss 0.2 dB, Breakdown Voltage 50 V, VSWR 1.20:1, Return Loss 20.83 dB. Tags: Connectorized, Inner DC Block. More details for DB-B1B25A-3G50V/H44-H4 can be seen below.