The Series 3800 Vehicle Intercom System is engineered to solve the problem of communicating in high-noise environments with a mobile vehicle platform. Fire apparatus, rescue vehicles, ambulances, command and control vehicles, airline deicers and paint stripers are but a few applications that currently benefit from the Series 3800 system. The U3805 is a passive module recommended for systems utilizing two or more radio interface headset stations. It is designed for permitting multiple Series 3800 Radio Interface Modules (a maximum of four) to be connected to one radio. The U3805 provides one output to a mobile radio, one primary input from a Series 3800 Radio Interface Module and three secondary inputs from Series 3800 Radio Interface Modules. With a modular design, rugged and weather-resistant enclosures and functional versatility, the Series 3800 intercom system is an ideal solution for any mobile environment requiring crisp, clear communication and effective hearing protection.