Product Features:   1.Measure Noise Dose / Exposure Time / Sound Level   2.Real time clock with calendar(TES-1355)   3.RS-232 interface(TES-1355)            Specifications:      Applicable standards  :  ANSI S1.25-1991, A weighting        Digital display:  09999%DOSE        Criterion level: 80, 84, 85, 90dB Selectable        Threshold level: Selectable from 70 to 90dB, 1dB step        Exchange rate: Selectable 3dB, 4dB, 5dB or 6dB        High level Detector:  115dBA        Peak Flag:  140dB        Measuring range: 70-140dBA        Accuracy:  ±1.5dB ref. 94dB @1KHz        Resolution:  0.1dB        Frequency weighting: A        Time weighting:  FAST , SLOW Selectable            Microphone:  1/2 inch electret condenser microphone           Power supply:  4pcs size AAA Alkaline Battery           Battery life:  About 36 hours           Dimensions:  106(L)×64(W)×34(H)mm           Weight:  approx. 350g (include batteries)                       Accessories                Instruction manual, Software for               WindowsTM, RS-232 Cable, 9 pin to               25pin Gender changer, Carrying case,               Calibration Screwdriver,               Windscreen.