Feature:1. Electronic stethoscope kit has high level of accuracy and sensitivity, is ideal to locate trouble spots within the engine block.2. Designed to identify the source of engine noise and faults, can diagnose the noise in seconds.3. Diagnostic tool to detect faults of engine, transmission, cat intake/exhaust manifold, fuel injectors, radiators.valves, fuel tanks.4. Suitable for all mechanics, electricians, engineers and breakdown service specialists, etc.5. Clear sound quality, allows the vehicle to be roadtested and diagnosed simultaneously.Specification:Item Type: Electronic Stethoscope KitMaterial: Stainless SteelSensor Type: Piezoelectric Acceleration TypeMaximum Sensitivity: About 800mv/gSignal To Noise Ratio: 60-120dbProbe Resonance Frequency: 24khzPower Consumption of The Whole Machine: <15mwNumber of Batteries: 2Battery Type: DC 9VBattery Model: 6f22 (Built-in Battery)Nominal Battery Capacity (Unit: MAh): 800Instructions:1. Insert the Plugs of the Six Probes into the Corresponding Input Holes (The Probe Colors Correspond to the Panel).2. Insert the headphone plug into the output hole, put on the headphone, turn on the amplifier knob, the indicator light is on.3. Gently touch the probe with your hand, you can hear the whistling sound from the earphone. adjust the amplifier knob to adjust headphone sound, the probe clip to the part of the machine that needs to be detected, and you can clearly hear the various vibrations of the machine from the headphone..Package List:1 x Host 1 x Headphone6 x Probe2 x DC Battery8 x Male and Female Belt