This is a very basic sound input sensor, it converts sound waves to electrical signal. Electret Condenser Microphone has a built in condenser (another name of capacitor) which holds electric charge, sound wave moves plate of condenser so capacitance changes and it creates voltage variation on its output.
Dimension 6x2.2 mm
Sensitivity(0db=1v/pa 1000Hz) -48 --- 66db
Current consumption 500uA
Opareting Voltage range 1.5 -- 10V
S/N ratio 58db