The OHP 170-4 from Beijing Ocean Microwave Corporation is a RF High Pass Filter with Frequency 170 MHz to 2 GHz, Insertion Loss 0.49 to 0.56 dB, Rejection 40 @ 109 MHz to 60 @ DC to 89, 3 MHz, VSWR 1.23:1, 1.50:1, Return Loss 14 to 20 dB. Tags: Module with Connectors, Chebyshev. More details for OHP 170-4 can be seen below.