WIDE APPLICATION: This sound level meter is suitable for monitoring sound quality in factories, offices, homes, schools, theaters, audio systems, and construction sites. MAIN FEATURES: Features maximum and minimum hold functions, data hold function, red backlit alarm and audible alarm, automatic or manual shutdown function, and temperature measurement function. 30-130dB: The measuring range is between 30 and 130 dB, making it ideal for measuring sound or noise. (The sound of a normal conversation is 40 to 60 dB). HIGH PRECISION: This sound level meter is a highly sensitive sensor that provides fast and accurate measurements. CLEAR READING: The product has a 4-digit display, making readings clearer and more convenient. Specifications: This instrument is a high-precision sound level meter with an accuracy of +/- 1.5 dB. 1) Measuring range: 30 ~ 130 dB 2) Frequency weighting: a-weighted 3) Max and Min hold function 4) Data storage function 5) Red backlit alarm and audible alarm 6) Automatic or manual shutdown 7) Temperature measurement function 8) Temperature unit selection (\"C\" or \"f\") Specifications: Brand: SMART SENSOR Model: ST9604 Measuring range --- --- 30-130dBA Accuracy --- --- ± 1.5 dB reference SPL point at 94 dB at 1 kHz Frequency weighting --- --- A weighting Frequency range --- --- 31.5Hz-8.5kHz Sampling rate --- --- 2 times/second Data hold --- --- Maximum and Minimum Hold Digital Display --- --- 4 digits Resolution --- --- 0.1dB Temperature measurement range --- --- -10°C ~ 50°C (14°F-122°F) Accuracy --- --- ± 2 Resolution --- --- 0.1°C Microphone --- --- 1/2-inch electret condenser microphone Power supply --- --- AAA batteries x 3 (not included) Package list: 1 * Sound Level Meter, 1 * User Manual