Close up view of the backside of the PCB

MEMS Microphone, Vesper VM3011 - World's First Adaptive ZEROPOWER Listening™ Digital Piezoelectric MEMS Microphone

Close up view of the MEMS Microphone

Switch/button operation is not documented

Power Shutoff Switch. When the bottom is rotated to access the batteries - this switch slides as the enclosure bottom is rotated to shutoff battery power to the PCB