HX-80N - Extremely Stable High Mount Outdoor Curtain PIR. The new HX-80N from Optex is an 80' x 6', high mount outdoor passive infrared detector that provides the stability and reliability necessary for an outdoor PIR sensor. The most important element in reliable outdoor detector is accuracy to distinguish a human from a small animal. The exclusive pyro element on board enables the HX to project an ideal detection pattern, thus allowing for more accurate detection of humans and less false alarms. In addition, the HX-80N's dual PIR's and 20 detection zones utilize the 'AND' detection pattern technology - upper and lower detection areas have to be activated in order to generate an alarm condition. This technology helps to prevent false alarms caused by a pet or small animal. The HX Series' detection length can be limited to avoid unwanted detection, and it's short range zones can be masked if needed. By limiting the detection range, false alarms due to unwanted movement (cars, persons or animals outside the protected area) can be eliminated. HX-80NAM - Includes Digital Anti-Masking. The HX-80NAM includes all the great features of the HX-80N but comes with a Digital Anti-Masking feature. When an object is placed close to the lens surface for a period of more than 180 seconds, the IR Anti-Masking circuit will activate and generate a trouble signal.