The thrane & thrane fixed mount unit is a single-channel fixed product for use on board a ship or inside a building. designed as a powerful add-on for maritime communication set-ups, it can also be integrated with a pbx system. the sailor sc4000 iridium telephone system is the ideal satellite communication solution and well suited for all types of vessels cruising the high sea from yachts to fishing vessels, from coasters to large merchant ships, from coast guards to naval vessels.