Sanitary telephone mouthpiece designed for candlestick telephones, glass with embossed picture of coiled magnet [GEC trademark], by GEC, c.1916. In original cardboard box, printed on one face with name of item and "Made in England. Cat. No. K7727" and on opposite face: "G.E.C. Everything Electrical".

There were some concerns in the early twentieth century around sanitation, health and telephony and whether diseases or infection could be passed via a telephone mouthpiece or earpiece, due to epidemics of tuberculosis and influenza around this time. People began to consider methods for providing a barrier protection against cross contamination that was thought to occur by sharing intimate objects, such as telephone mouthpieces. Several sanitary telephone mouthpieces, such as GEC’s K7727, became available to adapt to the transmitters of most telephones. These mouthpieces were made of glass or porcelain and could be sterilised by boiling in water. GEC’s K7727 glass sanitary telephone mouthpiece could be screwed into the handpiece or earpiece of a ‘candlestick’ style telephone handset and could also be easily removed and cleaned.

GEC’s K7727 'Magnet' sanitary telephone mouthpiece seems to have been available from around 1916 onwards, probably due to the prevalence of many infections and diseases around the time of the First World War, especially influenza and, from 1918 onwards, Spanish Flu. Due to the introduction of Bakelite telephones in 1930, the K7727 'Magnet' sanitary telephone mouthpiece was most probably disappeared from sale as it would only fit the candlestick-style handset.