Review on 🚦 Safety Technology International STI-34101 Solar Driveway Monitor Sensor - Wireless Alert Transmitter by Keith Aluguvelli

From 2011 I will order the 4th device. Two of these are installed along our 120 foot street. It detects any ferromagnetic object (iron or steel) that approaches it. Aluminum, animals, wood, etc. are not recognized. We had to replace a unit as it broke and worked on a hot sunny day. Some useful hints: if the block is pressed, it works, so it must be installed in a safe way. One of our blocks is 35 feet from a city street. When we placed it closer to the road, it would fire when a large car passed. Even now it still worked when a huge truck with earthmoving equipment drove by. Sometimes he missed a small car and a mail truck, those big, square trucks that looked like they were made out of fiberglass or aluminum and also drove far enough away from the machine not to be spotted.