PUI Audio SMT-0340 Micro Transducer measures only 3mm x 3mm, less than 1/6th the size of a dime. This tiny surface-mount transducer offers a relatively flat frequency response from 500Hz to 10kHz, allowing it to be used for polyphonic applications, or between 3.5kHz to 4.2kHz for peak output. PUI Audio SMT-0340 SMT Micro Transducer is designed for 3V0-p input, making it ideal for generating audible notifications on wearables and other small handheld electronics.