... :8MM-50MM hight quatity good serve Piezoelectric ceramic element Diameter:8MM-50MMDIELINESPECNo.ItemUnitSpecificationCondition1Resonant Frequency KHZ9.5±30%2Resonant Impedance Ω ... components such as buzzer(Piezo electric, electromagnetic, mechanical), piezoelectric ceramic element, SMD magnetic transducers, condenser microphones, ultrasonic sensor,Atomization piece, speakers ...