1?��Decibel Meter: Measurement range of 30 to 130dB with an accuracy of ?��5dB and frequency response range of 35Hz ? 8.5KHz. 2?��Large Screen: Our digital sound level meters are equipped with a high definition backlit 9.6in LCD screen, allowing you to easily read them at your convenience throughout the day. 3?��Wall Mounted: Sound level meter with mounting holes on the back, easy to install, widely used in homes, offices, hospital wards, hotels, laboratories and other places. 4?��Alarm Alert: The light flashes when the alarm is on, accompanied by a beeping alarm sound, and the alarm time and sound are adjustable. 5?��Alarm Clock Switch: Short press the horn button to turn off the alarm clock, the red light goes off, then short press the horn button to turn on the alarm clock, the red light is on.