A typical objective electronic sounder for hearth, security and industrial programs; the Sonos Sounder Beacon is certified to EN54. Provision of telephones suitable with hearing aids, marked with the conventional ear and ‘T’ image and equipped with inductive couplers and quantity controls. Listening to Enhancement Procedure Necessity: This document information https://www.firesense.co.uk/type/conventional-fire-system/conventional-sounders-vids-vads/