36 mm stainless steel; high‑accuracy quartz calibre (Cartier 115A noted in listings); steel bracelet; Ronde Solo de Cartier: steel bezel, silvered opaline dial with Roman numerals, railroad minute track with 24‑hour ring, blued sword hands, beaded crown with synthetic spinel, sapphire crystal; ~30 m WR; bracelet or alligator strap. Often seen cross‑tagged as numeric code 3603 on dealer listings.