 The main producers of these telephones were Western Electric (a unit of AT&T), Automatic Electric Co. (later acquired by GTE), Kellogg Switchboard & Supply Company, and Stromberg-Carlson.The first tube shaft candlestick telephone was the Western Electric #20B Desk Phone patented in 1904.In the 1920s and 1930s, telephone technology shifted to the design of more efficient desk top telephones that featured a handset with receiver and transmitter elements in one unit, making the use of a telephone more convenient.