What's the internal drive circuit? I need to provide it a square wave to generate a tone. The other white piezo transducer produces a current when I push it one way, and a reverse current when I push it another way. The black one generates no electricity. I changed the name of topic of this thread. Could this piezo buzzer respond fast enough to generate ultrasonic, or near ultrasonic tones (>= 17kHz)? I can still hear around 17kHz, according to a YouTube test. Also, do mosquitos actually keep some distance from you when you play a 17kHz+ noise?