... element Diameter:8MM-50MMDIELINESPECNo.ItemUnitSpecificationCondition1Resonant Frequency KHZ9.5±30% 2Resonant Impedance Ω350max±30% 3Static CapacitancepF70,000±30%At100HZ4 Input Voltage V1 ... (Piezo electric, electromagnetic, mechanical), piezoelectric ceramic element, SMD magnetic transducers, condenser microphones, ultrasonic sensor,Atomization piece, speakers and other audio components ...