Features:   1. Mini digital sound level meter with stable and reliable performance.   2. Wide measurement range from 30dB to 130dBA.   3. Data hold function, maximum and minimum value measurement.   4. Backlit LCD screen, convenient to use at night.   5. Low battery indication, automatic and manual shutdown function.   6. Compact and lightweight, comfortable to hold and carry.    Description:   AS804 sound level meter is widely used in noise engineering, quality control, health care and other environmental measurement work. For example, science and industry.    Specifications:   Model: AS804   Material: ABS plastic   Display: 5-digit LCD, maximum display 99999   Measurement range: 30 ~ 130dBA   Resolution: 0.1dB   Accuracy: 1.5db (under reference conditions)   Frequency range: 31.5Hz to 8.5Hz   Frequency weighting: A   About scope: LCD screen   WEIGHTING TIME: fast   Sampling rate: 2 times / s   Operating temperature: 0 ~ 40 ° (10% ~ 80% RH)   Storage temperature: -10 ~ 60 ° (10% ~ 70% RH)   Power supply: 3 x 1.5V AAA batteries (Not included)    Package Included:   1 set * sound level meter(battery not included)    Notes: 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 real object.