Product description: Model: ST9604 Measurement range --- --- 30-130dBA Accuracy --- --- 1.5dB reference SPLpoint at 94dB at 1KHz Frequency weighting --- --- A 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 measurement range --- --- -10C~5014F-122F) Accuracy --- --- 2 Resolution --- --- 0.1 Microphone --- --- 1/2inch electret condenser microphone Power supply --- --- AAA battery X 3 (not included) Package list: 1* sound meter, 1* instruction manual WIDE APPLICATION: This sound level meter is suitable for monitoring sound quality in factories, offices, homes, schools, theaters, audio systems and construction sites. 30-130DB: The measurement range is 30-130dB, which is very suitable for sound or noise measurement. (Normal conversation sound is 40-60dB). MAIN FUNCTION : With maximum and minimum hold function.Data hold function.Red backlight alarm and buzzer alarm.Auto or manual power off function.Temperature measurement function. CLEAR READING: The product adopts 4-digit display, which makes reading data clearer and more convenient. HIGH PRECISION: This sound level meter is a high sensitivity sensor, which is quick to measure and more accurate.