Indicator Buzzers with Tight Frequencies CUI Devices Indicator Buzzers with Tight Frequencies utilize piezo and magnetic technology with a built-in driving circuit. A narrow frequency tolerance of ±100 Hz allows for added frequency stability that is not affected by temperature or voltage. This provides more consistent tones and sounds in the given application. CUI Devices Indicator Buzzers with Tight Frequencies offer a highly reliable solution with a sound pressure levels (SPL) of 80dB, 85dB, and 88dB at 10cm, making them well suited for medical, smart home, and security applications that require tone consistency