Comet calls these "triplexers", but they are also referred to as combiners or splitters. They are basically band-pass filters, simultaneously passing RF in both directions through the common connector while the band-pass filters provide a high degree of isolation between ports. Band Pass - 1.3-150 MHz Ins. Loss: 0.2 dB Max Power: 600 watts PEP - 200-320 MHz Ins. Loss: 0.25dB Max Power: 600 watts PEP - 390-500 MHz Ins. Loss: 0.3 dB Max Power: 600 watts PEP Isolation: 40dB minimum Connectors: - Output: SO-239 - Low Pass: PL-259 w/coax lead - Mid Pass: PL-259 w/coax lead - High Pass: PL-259 w/coax lead