Aico High Output Remote Sounder is a powered electronic sounder for fire, security and industrial applications. The mains powered sounder connects into the alarm system, via a relay base or module such a the Ei428 or the Ei128RU. If the alarms trigger, the relay will send out a signal that triggers the sounder. The sounder emits between the frequency of 340-2900Hz with 32 different tones that you can select and has an output of 90-100dB(A) at 1 meter. The tone of the sound can be changed using the 6-way DIL switch.