Feature: 1. 2.7in large LCD display for easy reading, convenient to use. Wide measurement range from 30dB to 130dB, Frequency: 31.5Hz - 8KHz, Resolution: 0.1dB, Accuracy: ±1.5dB. 2. With A and C equivalent weighted sound pressure levels. Fast and slow dynamic characteristic mode. AC and DC signal output for frequency analyzer level recorder, FFT analyzer, graphic recorder, etc. 3. With maximum/minimum value measurement. 90-130dB alarm level setup range, it will hold the maximum value once the measured level is large than the alarm setup level. 4. Low battery indication, automatic and manual power off function. Equipped with sponge ball and a storage pouch. Compact and light, convenient to hold and carry. 5. Portable and easy to use, suitable for checking, monitoring or controlling the sound level for personal, families, business, studies, industrial, etc. Specification: Specifications: Material: ABS Accuracy: ±1.5dB (at the calibration point, 94dB@1KHz) Frequency Response: 31.5Hz~8.0kHz Dynamic Range: 50dB Measure Range: 30~130dBA, 35~130dBC Frequency Weighting: A weighted and C weighting Digital Display: 4 digit Resolution: 0.1dB Sampling Speed: 2 time per second Analog Bar Graph: One bar is 1dB, sample rate is two times per second Overload Alert: OVER or UNDER to show the stage AC Signal Output: 0.707V rms at FS, output impedance approx. 600ohm DC Signal Output: 10mV/dB, output impedance approx. 100ohm Time Weighting: Fast/Slow Microphone: 1/2 inch ECM type microphone Operating Temperature and Humidity: 0～40℃, 10%～80%RH Storage Temperature: 10～60℃, 10%～70%RH Power Supply(NOT included): 1 * 9V 6F22 battery or 9V 100mA DC adapter LCD Size: 52 * 43mm / 2.05 * 2.01in Item Size: 221 * 66 * 32.5mm / 8.70 * 2.60 * 1.28in Item Weight: 200g / 7.06oz Package Weight: 261g / 9.23oz Package Size: 24.5 * 9.2 * 5.2cm / 9.65 * 3.62 * 2.05in . Package List: 1 * Sound Level Meter 1 * Storage Pouch 1 * User Manual(English) Note: When measuring the noise in outdoors, please put a sponge ball on the microphone head to prevent the microphone from being blown directly to cause airflow noise.