The UT-2500 is a simple to use universal transmitter that is compatible with our 2500 Series products. The UT-2500 operates on a 3 volt lithium battery (included) and has several different methods of activation. The UT-2500 has a push button that can be used as a panic button or a wireless doorbell. There is also a magnetic door/window contact and terminals for both a normally open (N/O) and normally closed (N/C) input. These inputs can be used with any sensor contacts. Now you can have your favorite sensor send a wireless signal up to a mile back to the DCR-2500 receiver, depending on environment and terrain.