Kleartone was a mail-order house brand of Grossman Brothers of Cleveland, Ohio in the 1920s and 1930s. Most  Kleartones were archtop acoustics, but other types existed as well as banjos and mandolins. Kleartone guitars were made by the Regal, Gibson, Kay, and Harmony factories.

Source: Premier Guitar Magazine. KlearTone Jewel. Zachary Fjestad. March 16, 2007