Kay Kraft guitars and mandolins were made by Stromberg-Voisinet in Chicago from the 1920s onwards. Kay Kraft carried on into the 1930s and later as a brand of the Kay Musical Instruments Company which was established in 1931 from the assets of Stromberg-Voisinet. These Kay Kraft instruments are notable for their bolt-on necks and unusual Venetian body shape, but there were also conventional looking jumbo acoustic guitars and banjos.

Source: Kay Kraft catalog 1932

Source: Little Brother Blues -1930s Kay Kraft, Recording King, Deluxe and other bolt on neck designs