Sound Level Meter, Type 2, 30 to 130 dB dB Range, Frequency Range 25 Hz to 10 kHz, A, C, Flat Frequency Weighting, Accuracy 1.5 dB, Resolution 1 dB, Display LCD, 10 ms, 1000 ms, 125 ms, 35 ms Response Time, USB Interface, Microphone Type Electret Condenser, Microphone Size 1/2 in, Standards CE, Records Up To 1,024 Data Points, Operating Temp. Range 14 Degrees to 122 Degrees F, Built-In Microphone and Real Time Clock, Output Jack Analog, USB, (4) C-Cell Battery Type