... have high speed of detection, high precision and high sensitivity.specification:1,detection sensitivity: 2.5mm stell ball2,power supply: ... 3, power consumption: 270mW4, operation frequency: 22KHz5, operation temperature: -5 to 506, Net weight: 360g7, Dimension: 410 * 85 * 45mm8, package ... use a 9 volt rechargeable battery to power the detetor.It takes fout to six hours to fully charge the battery. The ...