A round, pebble-like case whose crown sits under a protective arch with a blue cabochon.
| Model | Reference | Case | Movement |
|---|---|---|---|
| Ballon Bleu 40 mm, steel | WSBB0040 | 40 mm | Cal. 1847 MC |
Specs and prices are approximate and current as of 2026; confirm details with Cartier or an authorized dealer.