The IS electronic sounder has been approved for use in potentially explosive atmospheres for Group I (Mining) and Group II (Above Ground) applications and incorporates a high Ingress Protected IP66 enclosure. The sounder unit incorporates a two stage alarm option and has a total of 32 selectable tones, selectable via a dip switch on the PCB and produces up to 105dB at 1 Meter. A specially designed time saver base enables quick and easy installation of this unit with no extra cabling to be made to the head of the unit. Connections are made to the base during the initial wiring phase which results in a faster more reliable installation. The sounder head simply twists and clicks into the pre-fixed base on commissioning avoiding any additional wiring and connections.