The Phonola 547 model is a radio receiver designed by Pier Giacomo Castiglioni, Livio Castiglioni and Luigi Caccia Dominioni in 1939-40 and produced in Italy by Fimi-Phonola of Saronno. The black radio has a very innovative shape: it recalls, in fact, that of a telephone set with a rectangular base and a projecting and slightly inclined loudspeaker, covered by a convex grille, with large cylindrical holes useful for increasing the diffusion in the environment of sound waves. When designing the Phonola 547, the designers took military devices as a reference for their small size, functionality and practicality. The intent of Fimi-Phonola, in fact, was to market a device that cost little, was made with cheap materials, but which did not neglect the attention to qualitative, functional and aesthetic aspects. The realization of the model 547 saw a great collaboration between the designers and technicians of Fimi, so much so that the development of the shape of the radio, which follows the arrangement of the internal devices, was the fruit of this cooperation. However, the perfect synergy between function and form, of the form that adapts perfectly to the content, enhancing its qualities, would not have been possible without the invention of plastic materials. The chassiss of the radio, in fact, is a mono die-cast shell in phenolic resin, the famous Bakelite, the first entirely synthetic plastic patented by Leo Hendrik Baekland in 1907 and also known as the "material with a thousand uses" for its numerous applications: from production of radios, alarm clocks, telephones, toothbrushes or jewelry.