Install motion sensors that not only sense movement but also distinguish the difference between the motion of a human body and any other disturbance to help eliminate false alarms. The Dual Technology Digital Detector combines a passive infrared (PIR) motion detector with a complementary active microwave sensor in a single hardwired unit for an accurate, false alarm-immune motion detector for maximum reliability. Ideal for use in residential and light commercial environments, the Dual Technology Digital Detector even allows easy customization for room size: When it's being installed, you can select the area to be secured from 20 to 40 feet. The Dual Technology Digital Detector implements a variety of patented technologies, including FM Digital Signal Processing (FM-DSP), which adjusts automatically based upon the room size selected, thus optimizing both PIR and microwave performance within the protected area. The PIR motion detector employs a cylindrical lens with uniform detection sensitivity beginning at 1.8 feet (0.5m) away from the detector up to a distance of 40 feet (12m). "True Motion Recognition"™ with Fuzzy Logic algorithm (TMR™) allows the NEXT DUO to distinguish between the true motion of an intruder and any other disturbances, which cause false alarms. An on-board motion event jumper determines whether 1 or 2 consecutive motion events will trigger an alarm to your hardwired security system. Additional features include a test input that permits switching the detector to the walk test mode remotely without removing the front cover. If you will be using this motion detector in an environment with pets, it is also available with pet immunity so that pets up to 85 pounds will not trigger the alarm.