Reliable quad active infrared photoelectric detectors, activates alarm only when two beams are blocked simultaneously EDC working mode reminds the user to check the detectors and prevent false alarms Advanced anti-crawl design Many adjusting methods, convenient alignment: indicating LED and buzzer besides view finder and measure voltage Convenient installation: LED display, buzzer, view finder, and voltage measurements Outdoor detection range: 250m Power: 10.5 to 28V/DC Maximum current: 165mA Temperature: -20 to +60 degree Celsius Storage temperature: -30 to +60 degree Celsius Alarm output: NC/500mA at 24VDC Tamper output: NC 1A/24V AC Alignment range: Horizontal: 180 degrees Vertical: 20 degrees Material of cover: black PC Weight: 1,300g