?High Accuracy?Wide Measuring range: 30~130dB , Accuracy: 1.5dB, Frequency response: 31.5~8.5KHz; Fast/Slow time weighting selection, display update time: 2 times/second (FAST), 1 time/second (SLOW); ?AC/DC Output?AC signal output: 4Vrms/ full barograph, output impedance is approx. 600 ohm. DC signal output: 33mV/dB. CE Certified RoHS Compliant ?Bar Graph Display?The LCD digital display can shows a 3-digit decibel level values, Auto Ranging Bar graph level, time and date. ?Dual Power?The decibel meter is dual power sullpy, can use AA batteries or USB cable, it will trigger a low battery alarm when the batteries are low power ?Wide Applications?The decibel meter is lightweight and easy to carry, widely use for office, classroom, noisy neighbour ,environmental measurement, law enforcement, work place design, sound level analysis of machinery and engines.