The NRX-SMT3 radio sensor is a battery-powered RF device designed for use with the NRXI-GATE gateway. It contains a wireless transceiver and is compatible with analog fire detection and alarm systems (using a patented compatible communication protocol). It is a multicriteria smoke and heat detector (58° C thermo-velocity). And an infrared sensor gives you greater detection capacity and greater immunity to false alarms. The sensor requires the B501RF base (not included) for installation. Certified according to EN54-25, EN54-5 (Class A1R) and EN54-7. Meets the requirements of 2014/53/EU for compliance with the RED directive.