The BLK-18W-S+ from Mini Circuits is a DC Block with Frequency 0.01 to 18 GHz, Insertion Loss 0.41 to 0.75 dB, Breakdown Voltage 200 V, Input Power (Avg) 33 dBm, Return Loss 16.5 to 23 dB. Tags: Connectorized, Inner DC Block. More details for BLK-18W-S+ can be seen below.