[High Performance] Resonant frequency 3.0~5.0+/- 0.5 KHz, resonant impedance 300 ohms max, low power consumption and high sensitivity.[Size] Piezo- pickup plate diameter 27mm/ 1.6 inches, thickness 0.3mm/ 0.01 inches; small, thin and lightweight, package: 5pcs x buzzer film.[] Made of brass and ceramic, temperature resistant, stable, durable and long service life.[Easy To Use] These pre-wired Piezo- pickups are easy to install, and other home-made instruments for sound and vibration detection.[Wide Usage] Perfect for beginner to use as touch-sensors, electronic drum triggers, buzzers, make your own contact mics, also used for watches, cameras, phones, electronic , computer, etc.
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