WIDE APPLICATION: This sound level meter is suitable for sound quality monitoring in factories, offices, homes, schools, theaters, audio systems, and construction sites. 30-130dB: The measuring range is 30-130dB, which is very suitable for measuring sound or noise. (The sound of a normal conversation is 40-60dB). MAIN FUNCTION: With maximum and minimum hold function. Data hold function. Red backlit alarm and buzzer alarm. Automatic or manual power off function. Temperature measurement function. HIGH ACCURACY: This sound level meter is a high-sensitivity sensor, fast measurement, and more accurate. CLEAR READING: The product adopts a 4-digit display, which makes the reading data clearer and more convenient.WIDE APPLICATION: This sound level meter is suitable for sound quality control in factories, offices, homes, schools, theaters, audio systems, and construction sites. 30-130dB: The measuring range is 30-130dB, which is very suitable for measuring sound or noise. (The sound of a normal conversation is 40-60dB). MAIN FUNCTION: With maximum and minimum hold function. Data hold function. Red backlit alarm and buzzer alarm. Automatic or manual power off function. Temperature measurement function. HIGH ACCURACY: This sound level meter is a high-sensitivity sensor, fast measurement and more accurate. CLEAR READING: The product adopts a 4-digit display, which makes the reading data clearer and more convenient.Specifications: Model: ST9604 Measuring Range --- --- 30-130dBA Accuracy --- --- ± 1.5dB of reference SPLpoint at 94dB at 1KHz Frequency Weighting --- --- One weighting Frequency Range --- --- 31.5Hz-8.5KHz Sampling Rate --- --- 2 times/second Data Hold --- --- Maximum and Minimum Hold Digital Display --- --- 4digits Resolution --- --- 0.1dB Temperature Measuring Range --- --- -10°C ~ 50（14F-122F) Accuracy --- --- ± 2 Resolution --- --- 0.1℃ Microphone --- --- Microphone 1/2inch electret capacitor Power supply --- --- AAA battery