Lightweight and portable, easy to carry. Easy to operate, equipped with leather, comfortable to use. With double alarm mode: light and sound vibration Automatically reset switch to the sensitivity function, so it is capable of detecting large, but also detecting small metal objects. May need to be adjusted according to sensitivity. Mainly used to detect metal necessary places, such as security day-to-day metal anti-theft examination, examination room, the school to bring communications tools to prevent cheating of the inspection work, as well as non-specified places, such as metal detectors Detection Sensitivity: Diameter 2.5mm Ball Power Supply: 9 V battery (6F22ND) (not included) Power Consumption: 270mW Operating Frequency: 22KHz The Working Current: Less than 50mA The Working Temperature: -5 ~ 55 Deg.C