It is a magnetic buzzer with a built-in oscillation source consisting of a magnet and a coil. The advantage of the magnetic buzzer is that it can achieve the ideal sound pressure level (85dBA) with low voltage and high current consumption in a small size (9mm), which is suitable for designs with small internal space and high sound pressure level requirements. It is available in sizes from 9 to 16mm, with voltage options from 1.5 to 24V, and with pin and SMT terminals.