If you look at the more traditional No. 5 Sonnerie, you see the early Dufour aesthetic that carried over to a lot of the Simplicities, with the moon/Breguet-style hands and Roman numerals. https://www.rlxwx.co.uk/Collection/air-king/ You'll also notice https://www.pnhwx.co.uk/Collection/luminor/ the switches on the right side of the case, operating the "Silent/Sound" and "Grand/Petite" selectors for the watch. This is the most traditional style of case design for Sonneries and https://www.rmwx.co.uk what was used for the No. 7 at Phillips.