Bird B Gone Sonic Shield pest deterrent scares animals and birds away from yards, patios, decks, balconies and other areas using a combination of sound and light. Sonic Shield pest deterrent features a motion sensor that triggers a loud dog bark and flashing LED light when a pest crosses its path. The unit is small, portable and operates on four AA batteries (not included). Place the product where you are having problems with birds and pests and watch them flee the area. This pest deterrent is the perfect choice when you have a variety of pests, many of which cannot hear ultrasonic noises. Bird B Gone Sonic Shield pest deterrent offers two protection modes. Day-time mode scares birds away through the combination of loud dog bark sounds and flashing LED lights. Night time mode is for use in areas where night time noise is discouraged and utilizes the flashing LED light feature to scare the animals and birds from the area.