Extech 407744 Sound Calibrator for 94 dB

Extech 407744 94dB Sound Calibrator features: 1kHz Professional Calibrator for 0.5" or 1.0" Microphones; 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/114dB is generated to an accuracy of 5% (frequency) and +/-0.8dB.