Class II Sound - Calibrator with different sound pressure levels, ±0.4 dB accuracy, frequency 1000 Hz for frequency evaluation A, B, C and D, 1/2 inch microphone opening, power supply via exchangeable batteries, sound class 2. The calibration frequency of the Class II Sound Calibrator is 1000 Hz and is a sine-wave form. Compared to other calibrators, this Class II sound calibrator has three adjustable sound pressure levels. 94 dB, 104 dB and 114 dB are available and can be selected by pressing a button on the Class II Sound Calibrator. Thus an additional 104 dB sound pressure level is available. With an accuracy of ±0.4 dB, the Class II Sound Calibrator is particularly precise. This makes it possible with the Class II sound calibrator to check the accuracy of sound measuring instruments and, if necessary, to adjust them. Optionally, the Class II Sound Calibrator can be equipped with an ISO certificate.With a battery life of 50 hours, the Class II Sound Calibrator has a particularly lon