Feature: 1. ACCURATE MEASUREMENT SOUND: Sound level meter tester is an instrument used to measure environmental noise. With digital technology, it can accurately measure the strength and frequency of sound. 2. WORKING PRINCIPLE: The Decibel meter's microphone will collect sound signals from the environment and convert them into electrical signals.The AD converter will convert the electrical signals into digital signals, which will then be transmitted to a digital signal processor for processing and analysis. The processor calculates the strength and frequency of the noise and displays the results on the screen. 3. WALL MOUNTED: Wall mounted decibel meter is wall mounted with mounting holes, can be mounted on the wall, convenient and does not take up space. 4. HIGH ACCURACY: Wall hanging type decibel noise measuring has high accuracy, wide measuring range, easy to use and portable. 5. WIDELY USED: Sound level meter tester can be widely used in industrial noise monitoring, environmental noise assessment, building construction noise monitoring and other fields. Specification: Item Type: Wall Mounted Decibel Meter Material: ABS Weight: Approx. 600g / 21.2oz Size: Approx. 23.7 x 12 x 2.7cm / 9.33 x 4.72 x 1.06in Wall Mounting Hole Distance: Approx. 8cm / 3.15in Sound Measurement Range: 30 to 130dB Microphone: Digital Microphone Accuracy ±1.5dB (at Reference Sound Pressure Standard 94dB 1KHa) Frequency Response: 31.5Hz to 8.5KHz Digital Display: 3inch Digital Tube Display (10.5inch Display) Power Supply: USB Power Supply (DC5V1A Adapter Shipping Without) Widely Used In: Home, Office, Clubs, Colleges and Universities, Classrooms, Hotel Rooms, Hospital Wards, Hotels, Laboratories and Other Places Common Problems: The Monitor Does Not Show (1) USB cable is damaged, replace the USB cable (2) power adapter damage, replace the power adapter Instrument Maintenance: The Clean of the Chassis: Alcohol, Diluent, Etc. On the Chassis, Especially the Window Has a Corrosive Effect, So When Clean, Gently Wipe with a Drier Damp Cloth Can Be.. Package List: 1 x Wall Mounted Decibel Meter1 x USB Cable