Product Name: Magnetic Transducer Buzzer with Pin 1.5V/3V/6V/9V Cheapest Electromagnetic Buzzer Model NO.: FBMMB2315 Brand: Saipwell Certification: ISO9001, CCC WORD nChannels: 7.1Channel Usage: Accept Radiation Mode: Direct Radiation Type Style: Mini Transducer Principle: Piezoelectric Earphone Cone: Polypropylene and Titanium Edge Transmission Mode: Bone Conduction Category: Buzzer Rated Voltage: 3VDC Operating Voltage: 2-5VDC Max. Rated Current: 30mA/3VDC Min.Soud Pressure Level: 85dB/10cm Resonant Frequency: 3.1