Place this motion sensor beside your main entrance, back door, or dressing room area. Entry chime can be self-standing, mounted easily to a wall, or installed at entry or exit locations. Unit detects motion up to 15 ft away, with choice of 2 different melodies or chime can be selected, with a switch-controlled adjustable high or low volume setting. Uses four "AA" batteries (not included). Measures 5" high, 3" wide, and 3" deep from front to back.