Electret Microphone - 20Hz-20KHz Omnidirectional : ID 1064 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: In-Ear Back Electret Microphone - Professional Mini Portable Omnidirectional Wired Headset Voice Audio Corded Condenser Mic w/ Cable Wire For Sennheiser System or Studio Mixer - Pyle PMEMSN12 : Musical Instruments
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