The new 418MHz Signature Series uses radio frequency technology, allowing you freedom and flexibility with outstanding features and increased range of up to 2,000 feet. Quickly know when you have visitors, telephone calls or emergencies with the bright flashing strobe and distinctive LEDs. This fire alarm transmitter with battery signals the Sidekick II Strobe Receiver that will flash to notify you in the event of a fire or smoke. Five year warranty. The model with the Fire Alarm Transmitter only needs to be wired into a home or building fire alarm system by supplying 12-24 volts from the fire panel. It should be installed by a licensed fire alarm company. Features: Supervision of up to 3 smoke or fire transmitters for low battery, malfunction or block path of transmitter Range up to 2,000 feet Low battery indicator What else do I need to make this work? This product will only work with 418MHz products in the Silent Call Signature Series. In order to be notified, you will need to purchase a Silent Call Signature Series Receiver.