SMART SENSOR AS844+ Sound Level Meter LCD Digital Decibel Meter Noise Monitor with Data Storage Function Item Type: Sound Level Meter Material: ABS, sponge Model: AS844+ Purpose: Suitable for noise measurement and monitoring in many industries such as traffic roads, automobile measurement, mechanical processing, home furnishing, reading halls, etc. Calibration Sound Source: 94dB at 1KHz Measuring Range: 30-130dBA / 35-130dBC Accuracy: ±1.5dB Resolution: 0.1dB Dynamic Range: 50dB / 100dB Overload Indication: OVER / UNDER Frequency Weighting: Characteristics A and C Digital Display: 3 1/2 Digits Analog Bar Graph: 1dB / 1 Bar Graph Sampling Rate: 20 Times/Sec AC Signal Output: 1 Vrms/Full Bar graph Dynamic Characteristics: FAST / SLOW Data Storage Capacity: 15000 Maximum Hold: MAXIMUM Automatic Power Off: After 10 minutes of inactivity Microphone: 1/2in Polarized Capacitor Power Supply: 3.7V Li Battery 1000mAh x 1 / USDB 5V Battery Life: 12 Hours (Continuous Use) Temperature Measurement Range: 0-45℃ Temperature Accuracy: ±2℃ Humidity Measurement Range: 10-99%RH Humidity Accuracy: ±5%RH