Piezo Stack Actuator, Fire Alarm Bell manufacturer / supplier in China, offering Piezo Elements Piezo Ceramic Disc for for Alarm Piezoelectric Buzzer Elements 23.5mm 3.2kHz FT-23.5g-3.2A4-Green Insulation, Piezo Elements Piezo Ceramic Disc for for Alarm Piezoelectric Buzzer Elements 23.5mm 3.2kHz FT-23.5g-3.2A3-Green Insulation, Piezo Elements Piezo Ceramic Disc for for SMD Buzzer Piezoelectric Buzzer Elements 20mm 3.6-4.5kHz FT-20n-4.2A1-21A-Green Insulation and so on.