Feature: 1. Mini noise meter with LCD display, accurate reading and quick response. 2. Can be used for sound quality control in various environments such as factories, schools, and buildings. 3. High sensitivity sensor, accurate measurement, fast and sensitive, convenient measurement. 4. The noise measurement range is 35dB-135dB, and the accuracy is ±2.0dB. 5. Digital noise meter, small size, easy to carry, stable performance and long service life. Specification: Item Type: Sound Level Meter Material: Plastic Model: MT-911A Battery: 3 x AAA Battery (Battery Not Included) Display: LCD Display Working Environment: Altitude Below 2000 Meters RH≤90% (No Condensation) Frequency Range: 31.5Hz-8KHz Sampling Time: 300 Milliseconds Dynamic Range: 50dB Accuracy: ±2.0dB Measuring Level Range: 35dB-135dB Size: Approx. 144x56x30.5mm / 5.7x2.2x1.2in. Package List: 1 x Sound Level Meter (Battery Not Included)1 x Manual Note: 1. Please allow 0‑1 inch error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.