The first Radiomir watch prototype was manufactured in 1936 for the Italian Navy and the watch went into production two years later. Today, the Radiomir collection still features the emblematic cushion-shaped case (47 mm and 45 mm), luminescent numerals and indexes, and a waterproof strap, sometimes in an extended version so it fits over the diving suit sleeve. Several years ago, Panerai presented the Radiomir 40, these models were inspired by the first Radiomir watch. Another feature that is so emblematic for Panerai, the sandwich dial, was also introduced to the Radiomir collection for the first time. The sandwich dial is made of two plates, the upper one, with indexes and numerals cut out, is fixed onto the bottom one covered with a luminescent layer.