I am looking for a devise to help me with this problem. My staff need to have a set of keys with them at work but they are constantly forgetting to return them at end of shift. The keys are to stay within 200 ft at all time. I would like a "tile" like devise that I can attach to the key ring, which would sound an alert when they leave a certain range. I dont need a gps finder app or anything with a monthly subscription. A simple transmitter/receiver system that beeps when the receiver gets out of range.\n\nAnyone know of some simple devise that would achieve this?