Brigade White Sound Reversing Alarm. “The safest alarms in the world due to their instant locatability and directional sound. The multi-frequency alarms are only heard in the danger zone. White sound reversing alarms are better and safer than standard alarms and will not cause a noise nuisance. This alarm gives an urgent but friendly ‘Shh…Shh…Shh…’ sound, thus eliminating a noise disturbance for local residents.”