Features: Precise Measurement: The sound level meter does not need to be touched, it can measure sound quality in various environments and display test results quickly and accurately. Sensitive Sensor: The sound level meter uses professional high-precision sensors with excellent sensitivity and accuracy. Its performance is stable and reliable. High Definition Display: Large, high-intensity LED-backlit display, able to cope with bright light, night and other conditions. Automatic Shutdown: This sound level meter has an automatic shutdown function and automatically turns off after 3 minutes of inactivity, protecting the environment and saving energy. Widely Used: This sound level meter is widely used in vehicle noise testing, industrial equipment noise testing and home noise testing. Funtion: Data retention function, measurement of maximum and minimum values. Low battery indication, automatic and manual shutdown function. Equipped with a sponge ball for sensor protection. Specification: Accuracy: 1.5dB Frequency range: 31.5Hz to 8.5Hz Measurement level: 30-130dBA Resolution: 0.1dB Time weighting: fast Power supply: 3 AAA 1.5V alkaline batteries (not include) Microphone: 1/2 inch electret condenser microphone Operating temperature: 0-40 Operating humidity: 10% -80% RH Storage temperature: -10-60 Storage humidity: 10% -70% RH Weight: approx. 111g / 3.9oz Size: approx. 155 * 50 * 25mm Package list: 1 * digital sound level meter Instructions for use 1. Open the battery compartment cover, enter 3 new * AAA batteries, close the battery compartment cover. 2. Press the start power switch button. 3. Wait until the LCD display is normal, can enter the test state. 4. You can press 'MODE' button to select 'MAX', then read the maximum noise. 5. Backlight switch button can turn the backlight on or off. 6. When the battery symbol appears, replace the battery for low power consumption instructions. Precautions 1.Do not use the device in high temperature and humidity environments. 2.If it is not used for a long time, remove the battery from the machine. 3.Once the device is used in the presence of wind, it is essential to mount the windshield so as not to pick up unwanted signals. 4.Operating environment condition: Humidity80% RH, temperature from 0 to 40.