6 PZ DC 3-24V Piezo Elettronico Buzzer, 12V Cicalino Elettronico Allarme Ecoscandaglio + 9V

6 PCS DC 3-24V Piezo Electronic Buzzer, 12V Electronic Buzzer Alarm Sounder + 9V Battery Snap Connector (3pcs T Type and 3pcs I Type). 6 × Piezo Buzzer. Made up by multivibrator, piezoelectric buzzer chip, impedance matching unit, resonator and shell.

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