Munters 800EZ Plugin Card allows you to connect your phone and outside temperature sensor to your alarm system. It has two quick connect pins that you can use to plug in your phone cord and outdoor temperature sensor. The card also has a "COM" terminal that you can use to connect up to two zones. If you are not using a siren, you can connect a 1.5KOhm 1/2W resistor between the positive and negative terminals of the siren or disable the siren monitoring function.