Look this high sensitivity alarm detector, you will get what you want! Infrared variable frequency bijection alarm detector system with LED voltage display. This Infrared Alarm Detector is ideal for observing visitors to offices, homes, shop, clinics and so on. Special infrared sensors used by the imported for signal detection, acquisition, use of advanced temperature compensation technology, micro-current technology, stable, reliable performance, according to the different needs of the user to change the time interval alarm detector system. In normal use, a 9-volt battery can be used for more than 8 months.The best alarm detector is a best choice for you. So what are you still waiting for?
Other Thoughts:This device works great. it is sensitive enough to beep if a leaf crosses it's path as it falls. It works flawlessly. If it had a vibrate function on the receiver I would give it 5 stars.