Vacuum Tubes made hearing aids a practical device for everyday use. The transistor made it into a practical and cosmetic device. Because most people did not want others to see the hearing aid miniaturization was a key factor to design and marketing. Assembly of hearing aids required excellent hand coordination as space was tight and parts were small. The Sonotone Corporation made the first transistor hearing aid (actually a hybrid) in 1952. This was a year ahead of the first transistor radio by Regency. On the right is the 1952-53 Sonotone 1010, World's First Transistor Consumer Product and Hearing Aid. Has one transistor made by Texas Instruments and two Sonotone designed subminiature tubes, as shown.