Batteries used: 9V 6F 22 Audio selection: four levels Probe sensitivity: -60db Audio amplification: 25000 times Working hours: 10 hours-23 hours Product features: All-metal body, fine workmanship, precision and high-end professional equipment. Superior performance, clear sound quality, strong sensitivity, imported components. Four gears adjustment to meet use under different conditions. The working principle of the instrument is to rely on the shock waves of the physical sound source to transmit the sound and gradually amplify the sound until it can be heard normally by the ear. The larger the leakage point in the water pipe, the better the effect. Additional functions: Function jack, which is the record recording function. Product specifications: current consumption: 13-33 mA; battery used: 9V 6F22 Working hours: 10-23 hours (depending on the strength of the sound) Four levels of audio selection: 3rd gear (100Hz-700Hz) 2nd gear (700Hz-900Hz) 1st gear (900Hz-1100Hz) 0th gear (1100Hz-1600Hz); Probe sensitivity: -60db, maximum audio amplification: 25000 times. Set accessories: 1 main unit, 1 probe, 1 earphone, and 1 instruction manual.