If your Santos came with papers dated 2024 or later, WSSA0071 is probably the reference printed on your warranty card. It is the current reference for the graduated blue dial Santos Large — the smoked blue that made the modern Santos famous — and because the number is new, most owners searching for it find almost nothing. This guide fixes that: the correct strap size, how this reference relates to the earlier blue Santos numbers, and the straps that genuinely work with a blue dial.
Cartier Santos WSSA0071 Strap Size and Fit
The essentials first:
- Reference: WSSA0071, Santos de Cartier Large model
- Case width: 39.8 mm
- Correct strap size: 21 mm, made for the Cartier QuickSwitch system
On the product page, select the 21 mm option. The strap clicks straight into the case — no tools, no spring bars, no contact with the lugs. A standard 21 mm strap from a watch shop will not attach to this watch; the QuickSwitch fitting built into the strap end is what locks it in place.
Don't let the reference numbers confuse you. Cartier has used three references for the blue dial Santos Large over the years — WSSA0013, WSSA0030 and now WSSA0071 — and they are the same 39.8 mm watch. All three take a 21 mm strap. The only blue Santos that doesn't is the Medium model (WSSA0063, 35.1 mm case), which takes 19 mm — covered in our Cartier Santos WSSA0063 strap guide. If you're not sure which you own, check the case width or the reference on your papers before ordering.
The Blue Dial That Changed the Santos
The Santos itself goes back to 1904, when Louis Cartier built a wristwatch for the aviator Alberto Santos-Dumont — square case, exposed screws, built for use rather than show. But for most of its life, the dial was silver.
The graduated blue arrived in 2019 and quickly became the Santos for people who found the classic dial too traditional. The sunray finish deepens from a lighter center to a dark edge, the Roman numerals are rendered in polished silver tone rather than printed black, and the sword hands are filled with luminescent material — details that push the watch toward sport without losing the Cartier signature. The faceted blue spinel in the crown ties it together, the case is rated to 100 meters, and Cartier's SmartLink bracelet and QuickSwitch system make it the most adaptable watch the brand builds. The WSSA0071 is simply the newest expression of that formula.
You Just Bought It — Now Protect It
Here's the thing about owning a new reference: everything in the box is still perfect. The bracelet has no hairlines yet. The blue alligator strap Cartier includes has never seen a summer. The first year of ownership is exactly when a third strap earns its keep — because scratches on a fresh bracelet hurt far more than scratches on a five-year-old one, and alligator leather ages fastest when it's worn daily from day one.
These are the most popular strap choices among Santos WSSA0071 owners:
1. Black Rubber – The Strap for Your First Summer
The WSSA0071 is water-resistant to 100 meters, but neither factory option wants to prove it: alligator should never get wet, and salt water is no friend to a polished bracelet. A black rubber strap for the Cartier Santos is the one that actually uses what the case can do — pool, beach, gym, travel — while both factory options stay flawless in the box. Matte black under a graduated blue dial is also simply a great look: it grounds the watch and lets the dial do the talking.
If you want the strap to echo the case, there's a version with the signature Santos screw motif and a new-style deployant clasp. Every Helvetus rubber strap is covered by a lifetime warranty — fitting for a strap whose whole job is taking the abuse so the rest of the watch doesn't.
2. Brown Leather – Navy and Tan
Blue and brown is one of the oldest pairings in menswear, and it works on the wrist for the same reason it works everywhere else: a warm strap gives a cool dial something to push against. A brown leather strap is the one direction Cartier's box never goes — steel and blue alligator are both cool-toned — and it turns the WSSA0071 from a sporty watch into a genuinely versatile one. This is the pick that changes the character of the watch most.
3. Blue Leather – The Everyday Version of the Factory Look
You already own a blue strap — but it's alligator, and alligator is for occasions, not for every day. A smooth blue leather strap keeps the blue-on-blue look Cartier intended while saving the factory strap from daily creasing and wear. Think of it as the working version of the strap in your box. And if you'd rather have the tonal look in sport form, the navy rubber strap with the Santos screw design does the same job with a lifetime warranty attached.
4. Black Leather – Maximum Depth
A graduated dial is darkest at its edge, and a black leather strap continues that darkness outward — the blue reads deeper and more saturated than on any other strap. This is the formal answer for the WSSA0071, and it's also compatible with the original Cartier buckle if you prefer to keep using it.
Every compatible option — more colors in leather and rubber, all in 21 mm — is in the full Cartier Santos de Cartier strap collection.
Keep the Bracelet — and the Links — Together
Many owners wear the Santos on a strap during the week and keep the SmartLink bracelet for occasions. If you shorten the bracelet, store the removed links with it: SmartLink makes them easy to take out, which also makes them easy to lose, and a complete bracelet always matters when a watch changes hands. The blue alligator deserves the same treatment — kept for the days it was made for, it will look new for years.
Final Thoughts
The blue Santos was designed to change — that's what QuickSwitch is for — and the WSSA0071 rewards owners who take Cartier up on it. Helvetus is one of the leading names in the aftermarket strap world, and our Santos straps are built specifically for the QuickSwitch system: an exact fit, no tools, no guesswork. Rubber straps carry a lifetime warranty, shipping is free worldwide with no import costs, and more than 50,000 watch owners already trust us with their straps.
The bracelet and the blue alligator came with the watch. The strap that lets you wear it everywhere is the one you add.
