Mass notification wide area sound signals up to 12km / 7 mile radius
KM3-165-WF Air Alarm
This is one of the most powerful wide area notification air horn systems you will find. It uses a proven maritime design of horn constructed in cast marine aluminium with a hermetically sealed stainless steel diaphragm assembly. SPL is 147 ± 1dB total at 1m and fundamental frequency 165Hz ±4Hz.