The MA40S4S with Audio Indicators & Alerts 10mm SENSOR SENDER is a series of extremely small, piezo-acoustic sensors manufactured by Murata. The MA40S4S is a type of piezo-acoustic sensor that is used to detect and monitor changes in pressure, or vibrations, within a range of 10mm. It is a self-contained module that utilizes a micro-electromechanical system (MEMS) microphone technology. It can detect sounds from under 0.06atm/ 1kHz to 10kHz and can be used for a wide range of applications including medical, automotive, consumer and industrial electronics. It is designed with a built-in amplifier and audio indicators & alerts. This sensor can be used for output control, noise cancellation, input monitoring, and other applications where pressure or vibration monitoring is required.