What makes Darley Sirens the industry’s finest? A potent combination of the latest technology applied to time-tested siren designs. Darley outdoor warning sirens are Omni-directional and distribute the siren’s full decibel output 360 degrees around the siren at all times. Another hallmark of Darley’s superior product is the use of continuous duty motors. Our siren motors are rated for approximately 10,000 hours of continuous, uninterrupted service. This means that there is no cooling period, no shut-down time. The siren works when you need it to work, period. Of course, all Darley sirens are backed by the industry’s longest warranty and best customer service.