The OHP 300-9 from Beijing Ocean Microwave Corporation is a RF High Pass Filter with Frequency 300 MHz to 3 GHz, Insertion Loss 0.84 to 1.16 dB, Rejection 40 @ 266 MHz to 60 @ DC to 251 MHz, VSWR 1.23:1, 1.50:1, Return Loss 14 to 20 dB. Tags: Module with Connectors, Chebyshev. More details for OHP 300-9 can be seen below.