This optional Antenna enhances the reception of your system. You can place it in an area where it has a clear view of the sky, such as your package tray, window, roof, etc.
This external antenna is not required for the GPS-50-2 sender to work... The GPS-50-2 has a built in antenna that will pick up GPS signals even when mounted under your dash - but this external antenna will cure reception problems and/or increase the stability of your speedometer if needed.
It is required for if you are using the GPS-50-2 sender to supply a signal to your cruise control.
