The Cartier Ballon Bleu WSBB0049 is the Ballon Bleu you can buy new today — the current 42 mm steel automatic with the silver guilloché dial, Roman numerals, blued sword hands, and the spinel cabochon floating beside the crown. Inside runs the 1847 MC; on the wrist sits Cartier's interchangeable steel bracelet, because the modern Ballon Bleu was redesigned around one idea: changing what it wears should take seconds, not a trip to the boutique.
That redesign is great news for strap lovers. The bracelet clicks off without tools, the strap mounting uses quick-release spring bars — and that means well-made aftermarket straps click straight in. This guide covers the correct size and the most popular Helvetus options for the WSBB0049.
Cartier Ballon Bleu WSBB0049 Strap Size and Fit
For the Cartier Ballon Bleu WSBB0049:
- Model: Ballon Bleu de Cartier, 42 mm, steel, current production
- Case shape: round, with the signature convex curves
- Attachment: spring bars (the interchangeable system's strap mounting)
- Strap width at the case: 20 mm
This means the watch requires a 20mm strap. When ordering, simply select the 20mm option on the product page.
As on every Ballon Bleu, the shape matters as much as the number: the case swells outward like a pebble, so a flat, generic 20 mm strap leaves gaps at the lugs and breaks the flowing silhouette. Helvetus Ballon Bleu straps are shaped to follow the curved case for a seamless, gap-free fit on the 42.
The Ballon Bleu, Finally Set Free
For years, changing a Ballon Bleu's bracelet meant tools, a watchmaker, and a wait. The current generation ends that — Cartier built interchangeability into the watch precisely because owners kept asking for it. The WSBB0049 is designed to live two lives: polished bracelet watch for the occasions that call for it, and strap watch for everything else.
The strap life has real advantages. Leather sheds the bracelet's weight across a long day, dresses the silver dial up beautifully, and keeps the steel bracelet pristine — which matters, because this is a current-production reference whose resale will always favor an unmarked bracelet.
The Best Straps for the Cartier Ballon Bleu WSBB0049
Helvetus offers leather and crocodile straps shaped specifically for the Ballon Bleu case. You can browse every compatible option here: Cartier Ballon Bleu Strap Collection.
Below are the most popular choices among owners of this reference, matched to its silver guilloché dial, blued hands, and polished steel case.
Blue Leather Strap
The signature Ballon Bleu move. Blue is already on the watch — in the sword hands and the spinel at the crown — and a blue leather strap carries it across the wrist. On the bright guilloché dial the effect is coherent, elegant, and unmistakably this watch. Blue Leather Strap for Cartier Ballon Bleu
Black Crocodile Strap
For full dress, black crocodile gives the 42 mm case the formality the bracelet only hints at. The scale texture against polished steel reads pure evening — the strap for dinners, weddings, and boardrooms. Black Crocodile Strap for Cartier Ballon Bleu
Black Leather Strap
Smooth black leather is the everyday workhorse: lighter than the bracelet, quieter than crocodile, and endlessly versatile with the silver dial. If the WSBB0049 is your daily, start here. Black Leather Strap for Cartier Ballon Bleu
Blue Crocodile Strap
The statement version of the signature color: dress texture in the watch's own blue. Rich against the guilloché dial and distinctive on the wrist — the pick for owners who want the modern Ballon Bleu to feel like theirs alone. Blue Crocodile Strap for Cartier Ballon Bleu
Final Thoughts
Cartier rebuilt the Ballon Bleu around effortless change, and the WSBB0049 rewards owners who take the hint. A well-fitted 20mm strap — or two — is all it takes to double what the current 42 can do, while the bracelet stays factory-fresh in the box.
Helvetus is a leading name in aftermarket straps for luxury watches, trusted by more than 50,000 customers worldwide. Every Ballon Bleu strap is shaped for a precise fit on the curved case, and all orders ship free worldwide with no import costs.
Find the perfect strap for your Ballon Bleu WSBB0049 in the Cartier Ballon Bleu Strap Collection.
