Our range of lightweight, flameproof sounders has been designed for the most hostile environments. Outputs of 103dB(A) to 118dB(A) at 1m are available. The range also includes a voice sounder which has the facility for up to 20 seconds of speech, recordable either by integral microphone or through an external source. In addition, a 'mechanical bell' sound is available - a lighter, corrosion-free alternative to a mechanical alarm bell.