Structure The Piezoelectric Buzzer Is Mainly Composed Of A Multivibrator, A Piezoelectric Buzzer Chip, An Impedance Matching Unit, A Resonator And A Shell. Meanwhile, The Multivibrator Is Made Up Of Transistors Or Integrated Circuits. When Turned On, The Multivibrator Vibrates And Emits An Audio Signal.Principle The Alarm Buzzer Is An Electronic Siren With Integration Structure. And, The Impedance Matcher Drives The Sound Of The Piezoelectric Buzzer. At The Same Time, Connected To The Rated Power, And The Buzzer Will Sound Continuously.Features The Electronic Buzzer Uses A Dc Power Supply. Meanwhile, The Active Piezo Buzzer Can Be Controlled Easily. And, Sound Pressure Level: 85 To 95 Decibels; Rated Voltage: 12Vdc; Operating Voltage Range: 3V-24V; Max Current: 10Ma.Wide Application High Decibel Continuous Sounder Is Widely Used In Computers, Printers, Copiers, Alarm, Electronic Toys, Automotive Electronic Equipment, Telephone, Timer And Other Electronic Products. 100% Satisfaction Guarantee If You Are Not Satisfied With The Mini Buzzers With Wires, Let Us Know Immediately So That We Can Issue You A Full Refund Of Your Purchase. If You Have Any Questions, Do Not Hesitate To Contact Our Customer Service.