Specifications: 1) Center frequency: 40±0.5kHz 2) Sound pressure level: 0dB=0.0002ubar≥115dB 3) Sensitivity: 0dB=1V/ubar≥ -65dB 4) Bandwidth: 2.0kHz 5) Beam angle (-6dB): 70 degrees typical 6) Capacitance: 2,100±20%pF 7) Metals of case: aluminum 8) Color: back 9) Max. driving voltage (RMS): 30Vrms 10) Working temperature: -20 to +70°C 11) Storage temperature: -30 to +8°C