1、High Resolution: 4 digit LCD display, resolution 0.1dB, clear writing, no ghosting, easy to read. 2、Auto Sensing Backlight: Humanized design, easy to view in dark conditions, more convenient to use. 3、Automatic Shutdown: It will automatically shut down after 15 minutes of no operation, saving energy. 4、Features: Measuring range meets daily needs, small size, easy to carry, and good hand held feeling. 5、Wide Application: For traffic noise, school noise measurement, home theater volume setting, home appliance noise measurement, etc. Item Type: Decibel Meter Material: ABS Model: DT-805 Battery: 9V 1 x 6F22(Not Included) Basic Parameters: Frequency Range: 31.5Hz~8KHz Range: 30~130dB Sound Level Frequency: Sound Level Frequency Weighting Microphone: 1/2 Inch Polarized Condenser Microphone Calibration: 1KHz Sine Wave, 94dB Signal Calibration Display: LCD Display Display Digits: 3-1/2 Digits Resolution: 0.1dB The Highest Number Displayed: 0.5sec Time Weighting: Fast Reaction (125ms), Slow Response (1sec.)Range: Low Range: 30-100dB, High Range 60-130dB Accuracy: ±1.5dB (under 94dB, 1KHz Reference Conditions) Alarm Function: when the Input Exceeds the Range, It Will Display "OVER" Maximum Value Hold Automatic Shutdown: After 15 Minutes Without Any Operation 1 x Decibel Meter 1 x User Manual 1 x Protective Box