Notifier B200SR-LF-WH sounder base

Notifier B200SR-LF-WH,white, low frequency sounder base is designed to meet the NFPA 72 sleeping space requirement to produce a fundamental frequency of 520 Hz +/– 10% with a square wave or its equivalent. Studies show that a lower frequency, centered around 520 Hz, is the most ideal to awaken sleeping occupants, even those with mild to severe hearing loss.