Alert yourself to the danger of fire with the Medallion Series Fire Alarm Transmitter-Contact Input. It sends a wireless signal to any Medallion Series Receiver when a fire alarm is activated. Designed to interface with a dry contact output-- it will transmit as long as the contact is closed and will stop transmitting when the contact opens. Operates on two AA batteries (included) and has a low-battery indicator light. Installation by a licensed electrician or fire alarm company is recommended.