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1kHz Professional Calibrator for 0.5" or 1.0" Microphones
Features:
    •Calibrates and verifies Sound Level Meter operation
    •LED indicator lights up when power is on
    •Level position to select 94dB or 114dB
    •For use on Sound Level Meters with 0.5" or 1.0" microphones
    •Durable die-cast, aluminum housing
    •1kHz sine wave at 94dB/114dB is generated to an accuracy of 5% (frequency) and ±0.8dB