This handset appeared via Australia Post Office and was to some degree manufactured in Britain just prior to 1939. During and after World War II these handsets were made in Australia. The handset belonged to the SEC Victoria and later the Kiewa Hydro Electricity Scheme. As this unit has a winder arm (to notify the switchboard) it would have resided in a workshop/machine shop and not in an office. The durability of the bakelite covering gave good protection in any environment. In years later the bakelite came in colours. This type of handset being able to endure rough handling was ideal for the surroundings of the alpine terrain. It would have been at the various outside outposts or foreman posts as swift communications was essential and communications with all sectors of work in the Hydro Electricity Scheme was mandatory, not only for safety reasons but also for efficient operational day to day progress. Also refer to article in "This Week" Newsletter 30th June 2023. Article attached to paper copy.This Australian Post Office 184 black coloured bakelite wall mounted phone was initially developed by Ericsson Telephones Ltd Britain. It was used by the SEC Office based at Mount Beauty and therefore has a winder (for power and notification to the switchboard. The hand piece (large ear and voice receptors)is placed vertically above the dial up winder.On the winder plate in hand writing is" turn handle lift handset" and below the handle "when finished replace handset turn handle"sec communications, wall telephone, internal communications kiewa hydro electricity scheme