Made of high quality plastic shell, safe and eco-friendly, durable and sturdy to use. Beautiful appearance, streamline design. Light weight, compact size, high sensitivity, bringing much convenience for you to operate. Detecting distance range is 3-20m /9.8-65.6ft, the sensitivity of this metal detector will change according to the detected objects size, volume, density and environment etc. It has two types of optional alarm mode: Audio mode (buzzer and red indication light) and vibrational mode (vibration and red indication light). Lower power consumption. It only need 1 x 9V 6F22 battery. And It also has alarm indication , yellow led (having detected object), flashing green led (machine starts to work), flashing red led (lower power).