... Internal oscillator buzzer -Buzzer alarm Magnetic Buzzer with Circuit Built in (Active circuit)(Diameter 12mm by Height 9.5mm, ... , piezoelectric buzzers, and speakers. The monthly output is 20 million pieces . Nowadays , it has about 500 employees ... applied for various kinds of alarms, satellite receivers , microwave ovens, computers, calculators, digital cameras, electronic dictionaries, ultrasonic ...