Sensitive Sensor: 0.5s response time, non-contact. Can measure sound level under any circumstances, quickly display the accurate measurement result. LCD DisplayLarge backlit LCD display, easy to read at night. Low radiation, reduce eye damage. Accurate Measurement: Measuring range 40~130dBA; accuracy 3.5dB dB with 0.1dB resolution. MultifunctionData hold function, max/min sound level measurement; 15 minutes auto shut-off, also has alarm function when the sound level is up to 130dB. Power Supply: Powered by 9V battery (included) Quantity: 1 pc Color: Yellow 1. Frequency Range: 31.5Hz~4kHz, Range: 40~130dB 2. Accuracy: 3.5dB (under 94dB, 1kHz reference condition), Resolution: 0.1dB 3. Frequency Weighting of Sound Level: A frequency weighting of sound level 4. Microphone: 1/2 inch polarized condenser microphone 5. Display: LCD screen 6. Display Digits: 3-1/2 digits 7. Response Speed: 0.5 seconds 8. Time Level: Fast response (125mS) 9. Alarm Function: "OL" is displayed when the input exceeds the range 10. Automatic Power Off: Automatically power off after 15 minutes without any operation 11. Battery: 9V carbon battery 12. Operating Temperature: 0~40 (32~140) Operating Humidity: 10~90%RH Storage Temperature: -10~60 (14~140) Storage Humidity: 10~75%RH