This instrument is designed to monitor sound quality in various environment. It can be widely used in noise control engineering, quality control, health and treatment, home environment monitoring, etc. Features: Mini digital sound level meter with stable and reliable performance. Wide measurement range from 30dB to 130dB. Fast and slow sampling rate for choice: 125ms or 1s. Data hold function, maximum and minimum value measurement. When measuring under MAX mode, the meter will only display the value greater than the current value; when measuring under MIN mode it will only display the value less than the current value. LCD display with backlight, convenient to use at night. Equipped with sponge ball. Specifications: Display: 4 digits LCD, Max Display 9999 Measuring Range: 30~130dB Sampling Rate: 125ms(fast mode) / 1s(slow mode) Operating Temperature: 30~40C(