This part is a kind of semiconductor called WM-61B.

Function of this product has Omnidirectional Back Electret Condenser Microphone Cartridge.

Manufacturers : Panasonic Semiconductor

Image and pinout :

Some of the text within the PDF file :

Omnidirectional Back Electret Condenser Microphone Cartridge Series: WM-61A WM-61 B (pin type) Microphone Cartridges I Features G Small microphones for gener al use G Back electret type designed for high resistance to vibrations, high signal-to-noise ratio G High sensitivity type G Microphone with pins for flexible PCB (WM-61B type) I Sensitivity Vs = 2.0V RL = 2.2kΩ –35 ± 4dB I Specifications Sensitivity Impedance Directivity Frequency Max. operation voltage Standard operation voltage Current consumption Sensitivity reduction S/N ratio –35±4dB (0db = 1V/pa, 1kHz) Less than 2.2 k Ω Omnidirectional 20–20,000 Hz 10V 2V Max. 0.5 mA Within –3 dB at 1.5V More than 62 dB I Typical Frequency Response Curve +20 +10 Relative Response (dB) 0 –10 –20 –30 20 50 100 200 [ ... ]

WM-61B PDF Datasheet Download