Description: Widely used to monitor sound levels with a measurment range from 30 to 130 decibels, accuracy ±1.5db, frequency response range 31.5Hz-8.5KHz Large LCD display screen, accurate to one decimal place, and also easy to read in distance Multifunctional usage, when the measuring value is over the alarm value( 30 - 130dB ), the meter will make a sound beeping and display the data Hanging designed to be applied in various occasions like factory, office, home, hotel, restaurant, library, hospital, shopping mall, traffic route etc. Audio Outlet, you can add external speaker by yourself, over a certain value, it can give an alarm Specification: Material: Plastic Measurement range : 30 - 130dB Accuracy: +1.5 dB (reference sound pressure level, 94dB @ 1kHz) Frequency response: 31.5Hz - 8.5kHz Microphone: 6mm condenser microphone Power supply: DC 5V 1A micro USB Working environment: 0 - 40 degrees (32 degrees Fahrenheit to 104 degrees Fahrenheit), 10 - 80%RH Storage of Temp. and humidity: -10~60C. 10~70%RH Overall Size ( L x W x H ): approx. 210mm x 130mm x 28mm / 8.26 x 5.11 x 1.1 Inch Package Includes: 1 Piece Hanging Noise Tester