20 pieces 3 V active piezo buzzer alarm sensor, electromagnetic beeper, alarm, for signal 9 x 6 mm / 5.5

Structural Composition The electromagnetic buzzer consists of an oscillator, an electromagnetic coil, a magnet, a vibration membrane and a housing. 3V DC power supply - 3V DC supply, suitable for alarm applications of various electronics Lightweight, convenient to carry and use at any time, very convenient and practical. Extensive use: widely used in computer, printer, copier, alarm, electronic toys, car electronic equipment, phone, timer, etc. Long term alarm: the buzzer emits a long term alarm with relatively high voice once it is turned on, safe and reliable. piezo buzzer 3.3v