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1kHz Professional Calibrator for 0.5" or 1.0" Microphones
Features:
    •Calibrates and verifies Sound Level Meter operation
    •Battery test position with battery status LED indicates if battery is good
    •For use on Sound Level Meters with 0.5" or 1.0" microphones
    •Durable die-cast, aluminum housing
    •1kHz sine wave at 94dB is generated to an accuracy of 5% (frequency) and ±0.8dB