Passive Infrared (PIR) sensor that includes a sophisticated short-range anti-masking system designed to activate an alarm when it detects any attempt to bypass the sensor by obstruction. Also noteworthy is the activation against possible attempts to manipulate or remove the sensor 24 hours a day thanks to the front and rear tampers. The MX-12FAM PIR detector performs a simultaneous analysis in two zones (Dual): horizontal and descending, thus avoiding false alarms caused by small animals, inclement weather and vehicles at the edge of the area. An important novelty is the double configuration that allows choosing between a detection of up to 12m, differentiating between the left and right area, with a 90º angle and configurable 180º coverage, with an output for the activation of a CCTV or additional devices. With its detection pulse count and sensitivity adjustment, the MX-12FAM PIR sensor is able to maintain operational stability even under extreme conditions.