Wireless Entry Sensor*works with MTC onlyReceive instant notifications if there is unauthorized entry on the boat. Perfect for securing lockers, doors, and hatches. Install the Wireless Module on one side of the door or locker and the Open/Close Magnet on the other side. Link to the MTC and receive alerts when the door or locker is opened or closed.Includes: Wireless Sensor Module Open/Close MagnetWireless Sensor Range from MTC is 150' @ 900MHz