The BLK-722N from Synergy Microwave Corporation is a DC Block with Frequency 3 to 900 MHz, Insertion Loss 0.15 to 0.40 dB, Breakdown Voltage 2500 V, VSWR 1.18:1, 1.45:1. Tags: Module with Connectors, Inner-Outer DC Block. More details for BLK-722N can be seen below.