Widely used to monitor sound levels with a measurment range from 30 to 130 decibels, accuracy 1.5db, frequency response range 31.5Hz8.5KHzLarge LCD display screen, accurate to one decimal place, and also easy to read in distanceMultifunctional usage, when the measuring value is over the alarm value( 30 130dB ), the meter will make a sound beeping and display the dataHanging designed to be applied in various occasions like factory, office, home, hotel, restaurant, library, , shopping mall, traffic route etc.Audio Outlet, you can add external speaker by yourself, over a certain value, it can give an alarmSpecification:Material: PlasticMeasurement range : 30 130dBAccuracy: +1.5 dB (reference sound pressure level, 94dB @ 1kHz)Frequency response: 31.5Hz 8.5kHzMicrophone: 6mm condenser microphonePower supply: DC 5V 1A micro USBWorking environment: 0 40 degrees (32 degrees Fahrenheit to 104 degrees Fahrenheit), 10 80%RHStorage of Temp. and humidity: 10~60C. 10~70%RHOverall Size ( L x W x H ): approx. 210mm x 130mm x 28mm / 8.26 x 5.11 x 1.1 InchPackage Includes:1 Piece Hanging Noise Tester