The first modern Panerai Radiomir watch honoring ref. 3646 from the late 1930s was the Panerai 'Radiomir Black Seal' PAM 183 launched in 2004. Equipped with a 45 mm stainless steel cushion-shaped case, this iteration was 2 mm smaller than the original Radiomir watches that had cases measuring 47mm in diameter. The new Panerai Radiomir 8 Days PAM 992 remains true to the modern Panerai spirit cased in a 45 mm stainless steel case.