This Ceramic Piezo Vibration Piece Sensor buffers a piezoelectric transducer that responds to strain changes by generating a measurable output voltage change which is proportional with the strength of vibration. So you can know the extent of vibration. Different from digital vibration sensor that only accounts times, this analog one can tell extent of vibration. Based on piezoelectric ceramic chip analog vibration makes use of the anti-transformation process of piezoelectric ceramic making the electric signals vibrate. When the piezoelectric ceramic shocking will generate an electrical signal, Controller analog port can be perceived slight vibration signals, Also can be realized with vibration interactions related works, such as electronic drums. Analog Ceramic Piezo Vibration Sensor Module 3.3V/5V for Arduino DIY Kit Working Voltage: 3.3V or 5V. Working Current: 1mA. Interface Type: Analog Output. Colour: As Shown Material: Metal Package Contents: 2set x piezoelectric sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.