PM-660U Paging Microphone
Designed for paging calls and general announcements, the PM-660U desk-top microphone comes with a large talk switch and a lock lever for easy and convenient operation. Its robust anti-vibration construction and balanced output render the microphone resistive to noise. In addition, the PM-660U microphone is equipped with a remote control switch (interlocked with the talk switch) for amplifier power on/off operation or chime activation.
Brand name(s) : TOA Electronics

Technical :
Type : Moving coil microphone
Polar Pattern : Unidirectional
Rated Impedance : 600 Ω, Balanced
Rated Sensitivity : -58 dB (1 kHz, 0 dB=1 V/Pa)
Frequency Response : 100 Hz - 10 kHz
Output : φ5.0 (φ0.2"), 4-conductor (2-shielded) cable (2.5 m (98.43")) without plug
Talk Switch : 1-push-to-talk switch, 1-locking lever, Short-off type
Remote Control : 500 mA or less at 30 V DC
Finish Microphone head: Zinc plated steel wire, gray baked paint
Main unit: ABS resin, gray
*** Do not keep the lock lever placed in the locked state (ON position) for a long period of time. Doing so may cause poor conductivity in the lever switch due to deterioration with age, resulting in unit malfunction.